Behavioral ecology of reintroduced Scarlet Macaws, Costa Rica

In October 2003, a study was launched to assess the success of our reintroduction program in the Punta Banco area. We set out to determine the extent to which they have adjusted to the release environment. Initially, this study was to investigate the following specific questions:

1. How many released macaws have remained in the area and which individuals form the groups?
2. What are the daily movement patterns of the macaws?
3. Is it possible to develop a system for the individual recognition of all the released Scarlet Macaws in the area?
4. What do the Punta Banco macaws eat and how does this compare with wild macaws, for example on the Osa Peninsula? This involves a description of the feeding patterns, an estimate of the variety of food sources used, and the identification of potential key species.
5. What are the threats to the long-term survival of released macaws in the Punta Banco area?

Summary of preliminary results

Amigos de las Aves has released a total of 13 Scarlet Macaws in the Punta Banco area with seven and six macaws being released in September 2002 and May 2003 respectively. With the second release of macaws, two distinct groups formed. A group of seven macaws (arbitrarily called the alpha flock) consists of two macaws from the first release and five macaws from the second release. Before reaching breeding age, macaws often form pair bonds with birds of either sex. This group thus subdivides into two male-male pairs (401 & 404, 740 & 754) and a group of one male (209) and two females (087 and 757). The second (beta) flock consists of three females and a male, all released in September 2002. One macaw from each release has moved out of our monitoring area. However, macaw sightings to the north of Punta Banco suggest that the two ‘lost’ macaws may still be alive.

Daily movement patterns

Both alpha and beta macaw flocks show strong roost site fidelity, usually returning to the same two areas to roost each evening. The two flocks roost in primary forests on large hills, overlooking the ocean. The alpha flock macaws leave the roost at 5:27 ± 0:07 (mean ± SD) each morning and return in the evenings at about 17:39 ± 0:13. The macaws are awake for approximately 12:11 ± 0:10 hours each day.

The movement patterns of the flocks are fairly consistent from day to day, but change gradually over time. During August 2003, the alpha flock spent 72% of each day in the release area (Tamsin Semrau, unpubl data). I found a similar pattern for November 2003 (77.2%, mean ± SD = 9.37 ± 0.974 hours per day, n=5 days where flock location was known for the entire day). After feeding on Beach Almond Terminalia catappa nuts in the early morning, the alpha flock macaws would move up to the release site by 7 am, where they would feed on Guava Psidium guajava fruits and rest for the day. As the number of available guavas in the release site decreased (in early December), the macaws began spending more time out of the release area and in the Beach Almonds (Figure 1). In mid-December, both flocks started to feed on guava fruits in the hills to the south of Punta Banco, usually in the mid-morning. The macaws generally feed in the same area each day, moving on once the food supply has been exhausted. Consequently, their morning movements are governed by the availability of Guavas and Beach Almond nuts.

Daily activity patterns

The macaws reach a peak in feeding activity between 5 and 8 am (Figure 2) and spend almost five hours a day feeding (average of 280 minutes). Their most frequent food source is Beach Almond nuts, which account for 80.5% of feeding observations. The reintroduced macaws have been recorded feeding on at least 19 species of plant in the area.

The macaws spend approximately 90 minutes each day engaged in autopreening and self-maintenance. An additional 21 minutes is spent each day allopreening where individuals, usually of a pair, preen each other.

Future research focus

The results so far, while being preliminary, have shown some interesting trends and provided useful insight into the daily patterns of the released macaws of Punta Banco. Future research will continue to investigate the original questions and will be aimed at consolidating our understanding of released macaw behavior. Of greatest importance is the generation of greater sample sizes. This would provide better insights both within and between observation periods. In addition, a larger sample size would provide the opportunity to evaluate differences between individual macaws. A promising avenue of investigation lies in the development and determination of dominance relationships within macaws.

Introduction

On March 4, 2004, seven scarlet macaws (Ara macao) were flown from the breeding aviaries of Amigos de las Aves, Alajuela to the release aviary at Tiskita Jungle Lodge, Punta Banco. These seven birds consisted on three males (aged between five years and five years eleven months) and four females (aged between three years one month and five years eleven months).

The release aviary is situated inland of the main lodge, atop a nearby mountain, and surrounded by jungle vegetation. The birds selected for release are maintained in this aviary for a period of time prior to release to assist in the acclimisation of the area, and subsequently, it is hoped, result in greater post-release success.

The Release Aviary

The aviary (15m x 5m x 2.6m) consists of a wooden framework, covered by chain mesh. Approximately one-third of the roof surface area is covered by sheet tin, providing shelter. Further shading is provided by nearby forest growth, however it is important to ensure that this growth not be allowed close contact with the aviary, and as such provide an access route to the aviary for snake and rat species. Tin footings surrounding the base of the aviary (to a height of approximately 1m) discourage these species from entering at ground level.

The aviary is furnished with adequate perching to accommodate all birds, however excessive perching in not supplied as this reduces the flight space available. Rather than providing an interconnecting framework of perches, the birds are encouraged to fly between perches, thus eliminating the risk of greatly reduced fitness prior to release.

Numerous feeding platforms are supplied, allowing for the dispersal of food among the group. The majority of these are under shelter, thus protecting both bird and food during unfavourable conditions. Drinking and bathing water is provided via a hose mounted on the roof of the aviary, which trickles continuously.

Maintenance of Macaws

Upon arrival, the birds must acclimitise to their new surroundings, such as the change in climate, vegetation and passing wildlife. To assist in this change, the food provided in the first few days greatly resembles the diet provided at the breeding centre in Alajuela. Only once the birds have become settled in the aviary are new food items (fruits and nuts etc. from the local region) introduced to their diet. This process is undertaken gradually, with new food species being trialled every few days. Feeding observations of the previously released scarlet macaws largely guided this selection, but other species are also tried, dependant on availability. Daily records are kept of the food offered to the birds, and of those foods they did or did not consume.

Once the birds are seen to consume enough variety of the local foods, and consume a diet somewhat replicating that of the previously released macaws (approximately 2 weeks following arrival), all foods that they would not naturally consume are removed from their diet. This includes food that they would not eat unless it is cut for them eg. oranges, food that they would not be able to access eg. adult coconuts, and the food unavailable to them following release eg. flour from the masa mix. By the third week, the beans, rice and peas of the masa mix are also removed from the daily diet. This then allows for a number of weeks prior to release in which to ensure that the birds can survive and remain healthy on a diet consisting solely of foods from the local region.

The macaws are required to associate these foods with the trees upon which they can be found. Fresh browse branches, generally of a feed tree species, are placed in the aviary daily to encourage the birds to forage for fruit or flowers. These are supplemented with branches of ‘spiked fruit’ for the feed tree species that can not be provided as fresh browse. Together, these branches give the birds practise in perching on branches not supported at both ends, and in manipulating fruit while doing so. Furthermore, fresh browse of both feed-tree and non-feed tree species enriches the birds behaviourally.

To imitate water access in the forest, a large Cecropia leaf is placed approximately 80cm under the dripping tap to collect the water before it runs off the leaf into a small pool below. However, due to unforeseen circumstance, the water supply to the aviary was cut in the third week to sixth week following the birds’ arrival. As water had to be hand-carted up the mountain on a daily basis during this period, a water bowl was provided. While this situation is not desirable for exposing the birds to the acquisition of water from vegetation, this inconvenience is not seen as a reason for concern.

The birds are fed twice a day during their stay in the release aviary. An early morning feed consists of fruits and nuts (and masa mix in the first three weeks), while the afternoon feed (3.30 – 4.00) provides sunflower seeds. While the masa mix was part of the daily diet, food was distributed between the feeding platforms and two dishes; these dishes were removed once the masa mix was no longer fed out. Food is distributed so that all fruit species are mixed, thus eliminating the potential for a dominant bird from consuming a favoured food item. It is at this morning feed that the ‘spiked fruit’ is also provided. The seed feed is timed to coincide with the seed feed provided for the previously released scarlet macaws, a procedure maintained to encourage these released birds to remain within the vicinity. It must be noted that the quantity of sunflower seeds provided to the birds at these feeds is only a small proportion of a macaw’s daily food intake, and thereby does not increase the dependence of the macaws upon this as a food source.

Fruit, nuts and flowers are sustainably harvested from the local region, with the majority of species collected from the property of Tiskita Jungle Lodge. Some species require collection daily, while others only every few days. This is greatly dependant on the period of time the fruit remains fresh eg. beach almonds keep for two – three days, whereas guava and garlic tree fruit last for only one day. Other fruits, such as the cashew nut fruit, are more favoured when ripe, so these are collected as individual fruits become so. This method of collection ensures that there is minimal wastage in fruit collection, and provides the birds with the freshest fruits possible on a daily basis.

The aviary is cleaned daily, immediately prior to, or following, the afternoon seed feed. All remaining food scraps from the morning feed are removed, and feeding platforms are scrubbed. This provides a hygienically better environment for the macaws, eliminates any reason for them to forage on the ground, and prevents any attraction of rats etc. throughout the night. Browse is replaced at this time as it remains fresher for a longer period of time in the cooler evenings and mornings; the birds are more active at these times to take advantage of this freshness; and there is no other food in the aviary for them, so fresh browse is of primary interest.

In order to monitor the acclimitisation of the birds, as well as their individual health, and any bondings or social structure that forms, it is important to be able to identify them as individuals as soon as possible. This has been best achieved based on physical characteristics such as beak colouring and cracking; patterns of blue throughout the yellow of the wings; and any other specific markings such as scars.

While behavioural traits can assist in identification, it must be remembered that these may alter in the company of particular individuals, may vary at different times of the day, and can be taught by one individual to another. To be able to monitor the health and condition of the birds daily, it is imperative that the recognition of ‘normal’ behaviour be attained so that ‘abnormal’ behaviour is instantly identified.

The birds showed no fear of humans from the day they arrived at Tiskita. As this is seen as detrimental to the successful release of these birds, they are discouraged from approaching humans, or recognising humans as allies. No physical contact is made with the birds, and any interactions with the birds are minimised to the two feeding periods per day. There are no humans in or near the release aviary at any other time of the day. As some of the previously released macaws spend time at the release aviary, it is hoped that the increased exposure to them, and the decreased time near humans, will leave the caged birds in a more favourable state for a successful release. Despite these efforts, the aviary birds have not altered their behaviour towards humans, or increased their flight response from humans.

To further encourage the presence of these previously released macaws into the release area, two aerial food stations are located within the vicinity (into which seed is placed each afternoon). Between two and five of the previously released macaws visit the release aviary on a daily basis. There are varying degrees of interaction between the caged birds and the released birds. The released birds spend the majority of the time perched on the structural beams of the aviary, on the roof of the aviary, or feeding in the nearby trees. However, there is occasional aggression exhibited towards the caged birds by the dominant male from the first release when his mate is on the ground digging. Since the digging behaviour of this female has ceased, aggression towards the caged birds from the male has also ceased.

May 2004
Lindell Andrews (BSc)
Release Procedure for Scarlet Macaws
Report to Amigos de las Aves

Seven scarlet macaws were transferred from the Amigos de las Aves breeding centre, Alajuela, to a release aviary at Tiskita Jungle Lodge, Punta Banco, on March 4, 2004. These birds were maintained in this release aviary during the acclimatisation process (refer to previous report for details).

The release aviary at Tiskita Jungle Lodge entails the large main aviary, in which the birds were kept during the acclimatisation period, and an adjoining smaller aviary (approx. 1m x 2m x 2.6m), interconnected by a small door of approximately 0.8m x 0.5m. This smaller aviary was to be instrumental in the release of the macaws, as it allowed particular individuals to be selected for release. For several days prior to release, the birds were allowed access to this smaller aviary during the afternoon sunflower seed, thus allowing them to become familiar with it. As the small aviary was only accessible during the feed, the birds associated access to it as favourable, as a sunflower seed ‘reward’ awaited them. When the time came to use this aviary to sort the birds for release, there was no difficulty in moving the birds from the large aviary to the smaller one, eliminating any need to physically stress the macaws.

As scarlet macaws are social birds, all birds were not released at once, as this may have resulted in the entire flock leaving the release site soon after release. It was thought that by releasing a pair of birds at a time, they would be inclined to stay in the area near the rest of the flock (still in the aviary). This belief was further enhanced by releasing birds every second day, rather than on subsequent days. By the time the final birds were released, the earlier-released birds would be comfortable in the area, and would choose to remain, thus encouraging the entire flock to remain in the area. This was to be important for future monitoring of the released birds.

Utilising this procedure of release, the releases occurred on May 18, May 20 and May 22, 2004. As scarlet macaws are diurnal birds, it was deemed best to release the birds in the morning, allowing them a full day to become accustomed to their new surroundings, and to ensure they had time to find an appropriate roost site for the night. It is important to note that had the weather been particularly bad (e.g. heavy rains or howling winds), the birds would not have been released. Following the early morning feed of fruit, nuts etc., the selected birds were separated from the rest of the flock using the small aviary, and then left to settle in this small aviary for half-an-hour before the external gate was opened for release. A feed station with a small quantity of sunflower seed was erected on a guava tree approximately 5m from the release cage. As the birds recognised the feed station as a source of food, it encouraged them to leave the smaller aviary. Following these procedures, the established pair of the group were released on May 18, followed by 2 on May 20, and then finally 3 on May 22.

In the days immediately following release, the birds did not leave the release area, despite macaws released in previous years coming and going from the vicinity. The birds were not particularly strong or accurate fliers in the first day, but this improved rapidly with practise. The birds were seen to forage for, and feed on, guavas within the first day, with some birds doing so within an hour of being released, an encouraging sign for future self-feeding. The birds, however, will have supplementary fruits provided until it is believed they can successfully sustain themselves. The sunflower seeds will continue to be fed to all released birds between 3.30 – 4.00pm every afternoon.

As of writing, some 11 days following the release of the final three birds, all scarlet macaws are doing well, adapting to their environment, increasing their fitness and foraging for foods.

October 2004 - February 2005
Jill Madison
Dominance hierarchy
Detailing the social behavior on the captive bred and Released Scarlet Macaws (Ara macao)
(In part only)

Introduction.

Amigos de las Aves has released Scarlet Macaws (Ara macao) at Tiskita Jungle Lodge during the period from September 2002 to October 2004, 23 of which attend afternoon sunflower seed feedings. During the period of November 2004 through January 2005, I observed social behavior at the feeding site, making note of behavior such as squabbling or chasing. Because each bird is individually identifiable by a combination of stainless steel band type, feather coloration and beak coloring, I was able to discern which birds were dominant in such interactions. From the behavioral observations, I have developed a dominance hierarchy, a model that interprets the social behavior and subsequently ranks 18 of the 23 birds (5 did not attend feedings enough to have conclusive data). I have also created an 'aggression plot', which demonstrates each birds individual level of aggression by plotting the number of aggressive acts observed against the number of other birds the said individual has acted aggressively toward.

Methods.

Social behavior was observed each day, during 15:00 to 16:30 at the feeding site, above the pre-release aviaries on the property of Tiskita Jungle Lodge. Sunflower seeds are distributed among 4 hanging metal feeders. During and after the feeding, each birds is individually identified by the observer and openly aggressive behaviour, such as squabbling or chasing, is noted according to the bird that emerged dominant. Each observed interaction is compiled according to the dominant bird, and lists the identification number of each bird and the number of times the aggressive interaction occurred (in Data Summary).

Results

The number in brackets ( ) indicates which release each individual is from.

The dominance hierarchy shows 18 of the macaws that have regularly attended the feedings during November 2004 through January 2005. The five remaining individuals, would presumably be ranked in the 4th tier, however remain independent of the main flock.

Discussion

Comparison of the observed dominance hierarchy of the captive bred and released Scarlet Macaws (Ara macao) at Tiskita Jungle Lodge to wild birds in the populations at Carara or Corcovado could elucidate the potential risks of aggression if any exist.

Data Summary

Among the 17 birds recorded for aggressive behavior,
the average number of attacks per bird is 9.9
the average number of other birds that an individual will attack is 4.8

April 2005
Dale Forbes, BSc, MSc
(in part only)

Releases

Eight macaws were released in April 2005 with the last two being released on 1 May 2005. Macaw (1) was released at the beginning of April, fed the following morning (at 04:55) but was thereafter only seen again 26 days later. When it returned to the release site, he was in excellent condition, both in terms of feather condition and weight. He was obviously well fed and presumably had found a patch of guavas and remained there for much of the time that he was away. Macaw (2) returned to the release site the afternoon after release.

In general, upon release, the macaws remain around the release cage, not moving much on the day of release. They appear to be somewhat dazed by being outside of the aviary and shy of the other macaws. Many of the macaws released remain in the immediate vicinity of the release site for a number of weeks before they venture out. If they are to leave the area soon after release it is most likely at dawn on the day after release. At this time, they will generally fly up on to the forested ridge.

Many of the macaws released in April 2005 found and ate guavas on the day of release. It is interesting that soon after release two macaws were seen feeding on green Nance berries. It is remarkable that they were able to locate a food tree outside of the release site so soon after release (particularly as they were never offered Nance in the pre-release aviary).

Feeding time in the release site

Between 8 and 16 macaws were present at the morning feeding (about 7:30 am) when various wild fruits were offered. Up to 22 macaws came in the afternoons to feed on sunflower seeds and at least 11 macaws came each afternoon.

Feeding observations

Macaws were seen feeding on at least eleven species of plant during April 2005. Guava remains the most popular food item for the released macaws and the number of feeding observations in the beach almonds continues to be much lower in 2005 than what was seen in 2004. The older macaws continue to utilise the almonds daily.

Solar eclipse

Punta Banco was at the very centre of a full solar eclipse in the afternoon of 8 April 2005. Interestingly, as the ambient light faded, the macaws began preparing to roost and had settled down 'for the night' in their various roosts by totality (16h15).

April 2005
Dale Forbes, BSc, MSc

Valuing what's around you:

How community support is ensuring the survival of the Scarlet Macaw

"Have you seen the macaws today?,"

The Scarlet Macaw was once found through 85% of Costa Rica, but capture for international trade and forest destruction has reduced the once numerous bird to only four localities. CITES restrictions have subsequently reduced the capture for international markets, but adults and nestlings continue to be taken for sale within Central America. Parrots are extremely popular pets in Costa Rica with the resplendently coloured Scarlet Macaw being the most prized and expensive of all. Driven by greed, a nest-robber needs to be able to find an active nest, and needs to have the support (or indifference) of the local community. Only through a community conservation ethic can the greed of a few be marginalised.

In September 2002, seven captive-bred Scarlet Macaws were reintroduced by ASOCIACIÓN AMIGOS DE LAS AVES in to the Punta Banco area of southern Costa Rica. It had been almost thirty years since macaws were last seen whirling through the canopy of the rainforests. Their return to the area signalled more than just the beginnings of a restoration programme but was equally a sign of a growing conservation consciousness amongst the people of the area.

The beachfront football pitch is at the very heart of the small village of Punta Banco and its 80 residents often collect to socialise around a game of football as the sun dips lazily into the Pacific Ocean. Behind the village, the land disappears into the hills of tropical rainforest and cattle pastures which extend to the unmarked Panamanian border, only 9 km away.

Two years ago, we started a project to monitor the released macaws more closely. Initially, this involved the establishment of a scientific protocol for data collection. We soon realised that keeping track of the movements of the macaws through hilly, forested terrain was incredibly difficult a six minute flight for the macaws would take us more than an hour to walk! It was like we needed eyes everywhere in the 15 km2 range of the macaws. "Have you seen the macaws today?," became our catch-phrase as we visited families and spoke with people everywhere we went. Sightings by locals were meticulously recorded and went a long way in developing a more complete view of the general ranging patterns of the macaws. Soon we noticed that the residents started to pay more attention to the macaws (noting flock numbers, direction of flight and time of day) because they were frequently asked about sightings. Then the unexpected happened.

The more the people noticed the macaws, the more they appreciated - and admired - them. And soon they started showing them off to friends and visitors and were visibly moved by seeing them. It appears that this appreciation stems not only from the macaws' physical beauty but also that the macaws have had some intrinsic value attached to them: to the people, they symbolise beauty and freedom, natural wonders and second chances. Every day, the macaws are seen over Punta Banco and yet still I see kids running out of the school's classroom to catch a glimpse of a screeching macaw as it flies by.

Conservation begins at home. To change, one needs to cultivate a development in the consciousness of an entire community (or population). This can only happen with regular interaction and reinforcement of conservation ideas and ideals, most effectively done by living the example. People and communities respond well to conservationists who are both passionate about their work and sensitive to the needs of the people. With this in mind, we live and work with the people of the area, trying never to preach but always willing to 'chat' about ideologies with our new friends. Volunteers and researchers are encouraged to meet as many people in the area as possible. We regularly call upon houses to meet the residents and ask/talk about the macaws, knowing that each new friend we make is not only a personal friend but also a friend of the macaws. This network of 'friends of the birds' (Amigos de las Aves) has the added benefit of having eyes everywhere watching for those who would harm the animals for their own benefit. It has been obvious that the appreciation of one species results in the deeper caring for nature as a whole. This concept has also worked in the macaws' favour as a result of the dedication of Tiskita Jungle Lodge and a local sea turtle conservation project. The entire consciousness of the community is evolving toward an appreciation of, and a desire to protect, the natural environment, and people who can see the intrinsic (or extrinsic) benefit of conservation will not hesitate to protect it.

The environment needs to have a value placed on it. We have found that the development of a conservation ethic amongst local people generates a value system based on the simple presence of species and ecosystems.

There are now 34 Scarlet Macaws gracing the skies of Punta Banco, ready to brighten the lives of the next generation of Costa Ricans.

October 2005
Dale Forbes, BSc, MSc
(in part only)

General distribution records

One bird has yet to be seen subsequent to release (28 April 2005) and one bird continues to be seen in the coastal zone between Tiskita and Punta Banco. All of the other macaws released in April 2005 are seen daily in the release site. Some might sleep in the forest adjoining the release site but the majority of the macaws sleep further up the ridge to the Northeast of the release site.

Health

Bird A is reluctant to fly and does not join the other macaws when they circle the release area.

Feeding time in the release site

An average of 15.6 macaws were present during the afternoon feedings.

Feeding observations

The macaws were only seen feeding on three species of plant in October 2005.

The macaws released in April 2005 had tended to remain in the release site for much of the day. The younger macaws are continuing to spend more time out of the release area. One Macaw ventured to a group of guava trees 1.4km away and has not been seen at the release site since October 10th. Macaws were often seen feeding in the beach almond trees.

May 2006
Ilona Thewissen MSc
(in part only)

Feeding time in the release site

2 to 7 macaws attend supplementary feeding on a regular basis. Other macaws attend on occasion, whilst some individuals were observed on single occasions.

The behavior at supplementary feeding is very hierarchy based. There are 4 feeders available and the dominance of the macaws that frequently attend appears to be three main pairs and one single bird. Flocking behaviour is noted.

General distribution

In the afternoons macaws are frequently encountered and heard in the release site and release site area, spending time feeding on plants. Macaws can be found during supplementary feeding time when flocking takes place in the area. The flocking behavior displayed is characterised by macaws flying back and forth above the trees, calling loudly, occasionally squabbling.

Macaws are seen every few days in Punta Banco and some are seen daily to the North.

Other sightings of macaws are documented in the area.

Feeding records

Macaws were seen feeding on Guava (Psidium guajava) and Tropical Almond seed (Terminalia catappa) amongst others, feeding records are limited to the release site area.

Breeding

Cavities have been documented throughout the area, and approximately 10 birds have bonded.

Health

All the macaws appear to be in relatively fine color and health.

September 2006
Helen Williams, Imperial College, London

I'm currently in my third year at Imperial College London, studying Biology With A Year In Research. As the name implies, this requires me to spend one year out of four working in a research institute of some kind in order to improve my practical science skills, gain a better insight into the scientific world and, hopefully, provide me with ideas and inspiration regarding my own future.

Having always been concerned with conservation issues and the role that biologists can play in protecting the natural world, I emailed numerous environmental organisations in an attempt to find one that would suit my interests. I was fortunate enough to have a good friend, Sophie Fauset, who was similarly looking for a placement that would fulfil our degree criteria, whilst simultaneously being interesting, challenging and useful. I was also keen to spend the majority of my time working in the field, knowing from experience that an extended lab session was not for me. Sophie found details about Amigos de las Aves and we were both struck by the organisation's passion for what they're doing and their enthusiasm for long-term field volunteers, as well as it being an almost-unique opportunity to work in Costa Rica with some of the most beautiful and charismatic birds around: Ara macao, scarlet macaws.

We contacted Marti Everett and passed on our details and were delighted when she invited us to temporarily join the team. Once we'd finalised the dates of our placement it was simply a question of passing the second year; booking flights; getting vaccinations; buying plenty of mosquito repellent and attempting to get to grips with Spanish. Apart from the last part, we did ok…

Before our departure we learnt that our brief was to monitor the behaviour of macaws that had been captive-bred at the centre in Alajuela and then released at a site called Tiskita, near the tiny pueblo of Punta Banco on the south Pacific coast. We would be working alongside Ilona Thewissen, a qualified biologist who has been studying that particular group for some time and who is well-acquainted with the area.

Upon our arrival Ilona gave us a tour of the surroundings, which are not only staggeringly beautiful but also home to an incredible assortment wildlife: monkeys and butterflies abound, as well as numerous mammals and literally hundreds of bird species, including, of course, the scarlet macaws released by Amigos.

Ilona indicated to us the types of trees favoured by foraging macaws and which sites they seem to frequent most regularly. We were also shown how to recognise whether they had recently been in the area by looking for cracked nuts and half-eaten fruit and to attune our ears to the distinctive sound of macaws feeding nearby.

We also learnt how to correctly provide the macaws with their "daily treat" of sunflower seeds. This occurs once a day at about 3.30pm in the forest above Punta Banco and, although unnecessary from a nutritional perspective, (all released birds are fully independent of humans) it offers them an incentive to remain in the area where they are safe from poachers and other negative human disturbances. It also acts as a social catalyst for the macaws by encouraging interaction between individuals and sub-groups and allows us to study these more closely.

This brings me onto what is the hardest but perhaps the most important skill we needed to grasp: how to recognise the different individuals. A combination of factors including facial characteristics; wing pattern; the shape and positioning of the bands (each is ringed at the centre with a flat or a round ring that can be on the left or the right leg) and their association with others means that each macaw can -theoretically at least- be differentiated from the rest of the flock. Clearly, this is crucial to our understanding of the hierarchies in this population, i.e. the social status of each bird in relation to the others. Scarlet macaws are highly social and constantly communicate and bond with one another, both vocally and through preening each other ("allopreening"), sharing food and fighting.

However, moulting feathers and changing allegiances between birds mean that constant surveillance is required to minimise the chances of an incorrect ID. It was decided that a computer file for each bird containing photos of the wing and facial patterns, which we could then regularly update, would help us to keep abreast of any physical changes. Meanwhile, constant monitoring their intraspecific (within species) behaviour meant that we were also aware of changing pairs and friendships.

As well as going to the places that we already know the macaws frequent, an important part of our work involves talking to local residents. The colourful plumage and noisy, gregarious nature of the macaws makes them popular and unmistakeable and the vast majority of people are only too pleased to inform us of their whereabouts. These tip-offs, combined with perseverance -and bit of luck!- have meant that we have a fair idea of where the most regularly-seen individuals spend their days. One of the challenges for the future will be to try and locate the more elusive birds too, this is particularly important in instances where we think they might be breeding The good news is that we know from the indigenous Guyami people that they're out there in the forest, the hard part will be finding them!

October 2006
Ilona Thewissen BSc
(in part only)

Management and Study of Reintroduced
Scarlet Macaws
(Ara macao)

Abstract

The Scarlet Macaw (Ara macao) used to be found throughout Costa Rica. Only two original substantial populations remain. 35 Captive bred macaws (parent and hand-raised) have been released in the southwest of the country over the course of five releases. A continuous scientific study has been carried out. The objectives are: to evaluate reintroduction success, to determine patterns of behavior in the process of adaptation to the wild, to determine the effect of subsequent releases, the total population size on dispersal and the development of social structures. Daily monitoring by tracking and "sunflower time" feeding are used to manage the population and obtain data on post-release behavior. The macaws are identified by their individual characteristics. The reintroduction project is a success with an overall survival rate of 91% and breeding attempts.

Background

Over the years 5 groups of macaws were released. The oldest macaws of the first release in 2002 are now approaching 10 years of age and the youngest macaws of the latest release in 2005 are approximately 3 years of age. The macaws released in 2003 and 2004 are aged in between. The flock is now starting to display a somewhat more natural age distrubution with very young macaws but also macaws well into breeding age. All the macaws have first spent about 4 to 12 weeks in a pre-release aviary at the release site in a private biological reserve in the tropical wet lowland forest along the pacific coast in the south of the country. In the pre-release aviary they become familiar with the local climate, wildlife and food, while human contact is strictly minimised to feeding and cleaning the aviary.

The macaws are closely monitored. Data is collected on a daily basis on all behavior aspects: dispersal (daily movement patterns, home ranges and site peferences for: breeding, foraging, resting, and socializing), foraging (species eaten, part eaten, seasonal changes) and social behaviors (pair and sub-flock formation, and type and direction of interactions). Identification of the macaws is based on their individual behavioral and physical characteristics.

Reintroduction success

Of the released macaws, all except 6 have been seen as recently as the past month (November 2006), an overall survival rate of 91%. All 7 macaws of the initial release have survived, which gives them a 100% 4 year survival rate.

Adaptation is defined in this study as the individual displaying natural behavior; being able to sustain itself physically and socially in the wild. It is researched by comparing behavior of wild macaws in, for example, Carara Biological Reserve and nearby Corcovado National Park, but mostly by the macaws' behavioral patterns and the changes in their behavioral patterns over time.

Dispersal and the bond with the release site

The time spent in the pre-release aviary and "sunflower time" feeding creates a bond between the macaws and the release site. "Sunflower time" feeding is one of the factors that maintains it. A bond with the release site is desireable because when the macaws keep returning to the release site and its surroundings, they remain in a protected environment and they can be monitored relatively easily. The bond with the release site has proven to be very strong. Nearly half of the macaws still go to the release site, mainly around "sunflower time" feeding time, and roost in the forest in the release site area. Moreover, all of the macaws can still be seen in the release site surroundings within a 7 km radius.

For nearly all the macaws "sunflower" feeding time in the release site seems to have become more of an important habitual social happening than an opportunity to get easy accesible food or a sunflower seed treat. The macaws that do attend normally feed for several minutes and then start a social display of joint flights and loud callings. On most days there are more macaws in these joint flights above the release site than actually fly in the feeding station and feed. Following this flocking behavior about half of the total population roosts in the forest around the release site. This shows that over time the function of the release site shifts from a site that feels safe and familiar and has food to more of a social meeting point at the end of the day. The timing of "sunflower time" feeding (late in the afternoon) encourages the macaws to roost near the release site as it is at the end of the day when the macaws seek to socialise more extensively, preferably in a flock, and roost.

Foraging

The four plant species that the macaws forage on the most are Guava (Psidium guajava), Jobo (Spondias mombin), Nance (Byrsonima crassifolia), Tropical Almond (Terminalia catappa). The presence of a substantial amount of dietary important plant species in the release site, facilitates the transition from being fed to foraging. At least half of the macaws diet seems to consist of Tropical Almond, which occurs abundantly along the beach and the costal zone where the macaws seem to spend most of their time. As the extent of the macaws' home ranges increases with the time they have been free, the number of plant species they forage upon increases as well.

Social behavior

Social interaction takes place whenever the macaws see each other. Macaws that are not in a pair or close sub-flock are most likely to interact vocally and by joint flights. They have a very strong preference to pair up with other individuals from the same release group. This bond also seems to influence other ways of social interaction. Social interactions like allofeeding, allopreening, food sharing and mating (attempts) take place almost exclusivly between macaws that were in the pre-release aviary together. Most of the macaws are part of several of these loose sub-flocks during the day to forage, rest and socialize. The total population can therefore be considered to have a rather stable core flock, situated around the release site.

January 2007
Sophie Fauset - Imperial College, London

"Coming back in January"

Returning to Costa Rica after a Christmas break in England was a very different experience from my initial arrival in late August. It was now January and many things had changed. My new found skills of sitting and waiting under a tree, and also knowing what to expect made the long flight much more survivable and relaxed. At the breeding centre I was able to see the 12 birds due to be released in Tiskita in the following months, and the next focus of the project. It was a good opportunity to meet the personalities and see the distinguishing features of the macaws that I would get to know a lot better, as well as photographing them all from various angles to aid identification.

During the 12 hour journey back to the release site in Tiskita Jungle Lodge, Punta Banco, requiring three buses (and due to a broken bridge, a lift in the back of a pick up truck) I was very anxious to get back to where had been my home for four months, and a beautiful paradise. The bus, a great prevention to increased tourism and further development to the area, was, as always, very long and bumpy. I was pleased to be on my way and the sight of the sea for the first time filled me with a contented glow, as did seeing my first macaw again. Having been in the very cold UK, I was very much looking forward to seeing the sun again, and was not disappointed. Now the Costa Rican summer it was hotter than ever. Despite constant application of sun cream it seems impossible to shift my red nose.

Once back at Tiskita, I noticed many changes from my previous time here. As it was breeding season, some of the pairs of birds had become more difficult to find and we were receiving reports of possible nesting activities. The behaviour of the birds give an indication of their intent.

In the birds that are not yet of breeding age there have also been changes in behaviour. Some are showing less fidelity to their daily routines and are not being sighted in the areas where they usually were regular visitors. It has even been noted that some pair bonds between birds have broken, with new bonds made with different individuals. There have also been changes in the macaws attending supplementary feeding, with birds present that have not been seen by me before.

The food available to the macaws has also changed slightly. The macaws seem to have two favourite food items, the seeds from the Beach Almond tree that grows plentifully along the coast line, and fruit from the Guava tree. Both of these plants are in fruit throughout the year, a very dependable food source. In addition to these foods the macaws eat seasonally available species, currently the flowers of the Balsa tree and Cashew fruits, other items, such as Jobo are no longer in season.

At present our birds are thriving and hopefully numbers will be added to by the fledglings of the breeding pairs in the next three to four months, a sure sign of the success of this project and the ability of hand fed captive bred birds to survive in the wild. This would be fantastic news not just for the scarlet macaw, but also for the conservation of all endangered birds.

February 2007
Ilona Thewissen BSc
(in part only)

Monitored feeding in the release sit

The identities of the macaws that attend monitored feeding in the release site has changed over the past weeks. Since May 2006 the macaws that regularly attended monitored feeding in the release site were: three pairs. Other macaws were seen on rare occasions like the pair of A (not since July 2006), macaws of the Clara sub-flock, and some single macaws.

Over the past weeks, more or less coinciding with the construction of the new pre-release aviary, the macaws that attended monitored feeding on rare occasions were seen more frequently. This is the highest number counted since at least May 2006. The main reason for this increase in macaws that attend monitored feeding is believed to be the curiosity towards the new pre-release aviary The macaws that were seen in the release site in February are: the five pairs, the sub-flock of 6 birds with another macaw and approx. 5 other macaws.

Most of the macaws do seem to attend monitored feeding time to feed on the sunflower seeds, however the majority of the time is spend socializing with all the other macaws in the release site, mainly by vocalization, chasing and joint flights.

Pairs and sub-flocks

The pairs and sub-flocks seem to remain mostly stable.

Dispersal

Macaws are seen over 25km away from the release site both Southwards and Northwards of the release site. Locals living in these areas report that they see several macaws very frequently to nearly daily. Most of the macaws do seem to still have their home range within a 5km radius from the release site because 24 individual macaws have been seen these past months. This implies that although some of the macaws do go to sites over approximately a 30 minute flight away, they still come back, most of them to Tiskita.

March 2007
Michelle Eglinton

"From a Zoo Keepers perspective"

The tropical rainforest situated in Tiskita is the perfect location for reintroducing Scarlet Macaws back into their natural habitat. Having worked at the breeding centre in Alajuela for the past three months, I was sent to Tiskita to check out preparations for the next release as well as assisting the biologist with observations of the pre-released macaws. I found Tiskita to be a beautiful area that is perfectly suited for macaws. The monitoring and continued observations and by our biologists and volunteers, to be extremely useful in collating data for our project.

With another release planned for the near future the building of a new release cage is already underway. The old cage finally disintegrated and 'died' and so a new cage is being built at the same location and its preparation is causing great excitement amongst the wild macaws, with many sightings of birds that had not been seen in that location for a while.

Plenty of fruit trees, such as Guava, surround the cage so initially the birds do not have to fly far to find food. A small "treat size" amount of sunflower seeds is provided at the same time daily (4pm) to encourage birds to return to the site so they can be easily monitored. This has been carried out since the first release and is still provided today. Because of this, many of the birds still return to the release site every afternoon. The site is private from locals and tourists and only a small number of people are permitted in the area, this is mainly the biologist, volunteers, the workers that are constructing the cage and the owners of the reserve.

Close monitoring and observations are very important for the release, not only to evaluate the success of the release program, but to collect data on all behavioural aspects, including social behaviors and interactions, daily moment patterns, home ranges, site preferences and foraging.

In order to do this, Amigos de las Aves current biologist Ilona Thewissen has her work cut out. As we do not like radio trackers, and flight paths are impossible to follow, preferred sites are found by information from locals and hours spent watching and listening for macaws. Once these are found, Ilona and her volunteers walk through the forest for hours, sometimes taking a few days to reach sites, where macaws are rumoured to be seen or to have possible nesting sites.

During my time spent at Tiskita, Ilona was very dedicated to the macaws and her observation skills were excellent. Individual macaws are identified by their faces and the markings on the wings. I found identifying the macaws not to be an easy task as many of the birds have very similar patterns on their wings and stayed high up in the trees. I was very impressed that Ilona knew all the birds by sight and could tell me the band numbers of all the macaws that I saw. While many Zoo Keepers would be able to do the work that Ilona does, having a biologist on site with Ilona's skills is a definite advantage.

It is interesting to compare the skills of a Zoo Keeper (with much more hands on and close-up experience) to a biologist (who mainly work with only textbook knowledge). Ilona is excellent at observations, collating and analysing data. I couldn't even begin to do this. However, when it comes to caring for birds due to be released, having a zoo keeper on site is a definite advantage. Scientists, are not normally able to handle birds and they have little knowledge and no experience of what to do should one of the birds become sick or injured. Therefore, when a release is due to take place, a zoo keeper should be present to care for the birds until they have been released and are considered to have adapted well.

Being a zoo keeper, I am biased, we do have a greater knowledge of avian behaviour. Having worked with birds in close proximity for many years, I generally can "read" a birds behaviour very well. For instance, most people are unaware that birds are sick, until they are practically falling off the perch. They are notorious for concealing injury and illness, which makes treatment even harder to carry out. Whereas working in the field, biologists cannot always identify the "smaller and significant" behaviours that they are seeing and often misinterpret them.

There are currently two biology volunteers at Tiskita. Students from England, Sophie and Helen have been at Tiskita since August 2006. Both girls are working really hard and put in many long hours in their work for us. Again, it is easy to see that they have no practical experience or knowledge with birds. Having said that, the girls are still at university and study for their masters degree, so they are learning heaps in Tiskita, giving them a basis of "field study work" which will help them in their chosen careers.

After nearly 8 months, they are able to identify some of the birds but still are unsure of many of the behaviours that they are seeing. Sophie and Helen have been helping Ilona greatly in doing basic tasks such as monitoring the sunflower 'treat' feeding, which is used to encourage birds to return to the release site, to enable monitoring of numbers and health, also to encourage roosting in a safe area. The girls also monitor foods, possible nesting sites and input of data onto the computer, giving Ilona more time to go to other possible macaw locations.

We are very luck in that we believe that we have found the best of both worlds, with biologists and keepers working together - asking questions - and comparing findings and knowledge.

March-August/September 2007
Tiskita status report of conservation and research

In part only

Ilona Thewissen, M.Sc.
Head field biologist, Associación Amigos de las Aves

New release

In March 2007, 10 new Scarlet Macaws were brought over from the breeding centre to the in-situ pre-release aviary in the release site in the Tiskita rainforest. They make up the sixth release.

The new Scarlet Macaws stayed in the pre-release aviary for about two months to acclimatize. They were then released in May.

Adaptation and integration

So far, the new release can be considered successful with all the newly released Scarlet Macaws surviving. They seem to have adapted well, are self-sustaining and socialize with each other and the previously released Scarlet Macaws. They have only slowly started to expand their home range from the release site.

Inside the pre-release aviary, the new Scarlet Macaws quickly got used to the locally collected food items that were put out for them every morning. They were given any flower, fruit and seed that is known to be part of the Scarlet Macaw diet and that was in season at the time. This implies they were mostly given the following 13 species:

Anacardium occidentale (Cashew fruit)
Averrhoa carambola (Carambola)
Byrsonima crassifolia (Nance)
Cocos nucifeda (Coconut)
Inga laurina (Inga/Guava)
Magifera indica (Mango)
Miconia sp.
Musa paradisiaca (Banana)
Ochroma lagopus (Balsa)
Psidium guajava (Guava)
Spondias mombin (Jobo)
Syzgium spp. (Water Apple)
Terminalia catappa (Tropical Almond)

Within a few days they mastered opening the hard shells of the Tropical Almond, which then became their preferred food item. It is one of the most commonly available plants they can forage on year round. For the first two months following their release, they were given locally collected food items in the morning in the release site. This "soft release method" is used to reduce stress on the newly released Scarlet Macaws while they deal with the transition to the wild, but it is also used to develop and maintain their bond with the release site for integration and monitoring purposes. Entering the fifth month following their release, all the new Scarlet Macaws seem in good health and have been seen foraging on a variety of species.

Three of the newly released Scarlet Macaws disappeared from the release site directly following their release. However, after 3 months two of the formerly disappeared individuals returned to the release site. One only returned for a day and left again, but returned again a month later with the third formerly disappeared individual and they seemed to have become a pair.

Age distribution

The Scarlet Macaws are generally between 2 to 5 years old when they are released. The age distribution at present comprises individuals in the range of 2 to 10 years.

Figure 1. Age distribution by intervals of 2,5 years.

All individuals are 10 years or younger, the population is therefore overall a relatively young one. Successful breeding attempts are only likely to occur in the age category of 7,5 years and above. Reintroduced captive-bred Scarlet Macaws especially may experience a longer learning curve for successful breeding, because they first had to spend time adapting to the wild and they have not experienced parental skills on them in the wild. For reproduction see Reintroduction success.

Sex-ratio

The sex-ratio of the maximum number of released Scarlet Macaws still alive is 20(?):21(?) and also includes the individual that is believed to have been shot in Punta Burica because its identity and therefore sex remain unknown. With the last release, as with each new release, it was strived for to maintain an equal sex-ratio.

Reintroduction success

Reintroduction success is measured by survival and reproduction.

Survival rate

The overall survival rate is 93%. The overall first year survival rate is 98%.

The survival rates being high, natural population expansion will be the key to long term success of the reintroduction project.

Reproduction

No successful breeding attempts were observed so far. The population number would easily increase to over 50 in the next few years with further releases and the addition of some young if breeding attempts will become successful. This implies that long term reintroduction success is nearly secured for.

Research

Research will continue as at present. It continues to focus on the behavior and ecology of the released Scarlet Macaws. Data is collected on a daily basis and is being stored in the database for analysis.

Future goals

New releases

New releases will continue. The addition of more Scarlet Macaws stimulates pair formation, increases genetic variability and ensures overall population viability. The reintroduction project's location seems to have a carrying capacity for several hundreds of Scarlet Macaws. It has vast areas of primary and secondary rainforest, alternated by pastures with diverse vegetation.

Tree planting project

Due to climate change, the beach in the area is eroding. This implies that with time, the released Scarlet Macaws preferred food source availability, the Tropical Almond, is going to be drastically reduced as it occurs predominantly in the coastal zone right at the beach. The Tropical Almond is not endemic to the Neotropic zone but has become widespread all over this zone. Its potential reduction would therefore not impose a problem for the Scarlet Macaw. However, it is considered to start a tree planting project to ensure the released Scarlet Macaws can keep foraging on Tropical Almond in the future. Several thousands of sprouts that can be find below trees of the species would be collected and grown in a tree nursery.

Local people that have properties away from the beach would be approached to allow for some trees to be planted on their property. As most local people (Costa Rican, Native American and foreign) greatly enjoy having Scarlet Macaws around, it is thought that there will be sufficient cooperation.

Education

Although the project is well established, well known and generally respected, new information sheets will be handed out again with general information about Scarlet Macaws, the project and guidelines how to protect the released Scarlet Macaws.