THE HUSBANDRY, BREEDING AND EUROPEAN REGIONAL STUDBOOK OF THE RED-SPECTACLED AMAZON AT LORO PARQUE

BY ROGER G. SWEENEY

The red-spectacled amazon (Amazona pretrei) is currently maintained in four zoological collections and by two known private keepers in Europe. A first edition of the European regional studbook showed a living population of 61 birds held between the four zoological gardens currently working with this species (Sweeney, 1997b); breeding is now becoming increasingly successful, and within the next five years several more locations should be able to receive and work with it. The wild population is considered to be declining and is listed as Endangered in the IUCN Red Data Book (Collar et al., 1992) and in Birds to Watch 2 (Collar et al., 1994). Field work on this species suggests that the primary reasons for its decline are habitat disturbance and illegal trade in live animals as pets (Varty et al., 1994). Work is now being conducted to prevent any further illegal trade and to ensure that the most important regions of the species' range receive some degree of protection. In captivity the red-spectacled amazon has been included in European zoo collection planning for amazon parrots, and a petition to form a European regional studbook was applied for and approved in 1996 (Sweeney, 1997).

The red-spectacled amazon is a full species within the genus Amazona, although previously some authors placed it as conspecific with the Tucuman amazon (A. tucumana). It measures 31 cm in length (Forshaw, 1989), and body weight, measured from several adult birds at Loro Parque, shows an average of 275 grams (Sweeney, unpublished). Forshaw (1989) gives a detailed description of the plumage; some degree of sexual dimorphism is evident, with the male having a greater extent of red over the forehead and always more extensive red coloration on the carpal edge of the wing and the under-wing coverts. In juvenile birds sexual dimorphism is not clear, as immature male birds have reduced areas of red coloration until they are three or four years old.

The wild population is regarded as endangered (Collar et al., 1994). A field study (Varty et al., 1994) estimated a remaining wild population of 7,500 to 8,500 birds, with this population being now almost entirely confined to the Brazilian state of Rio Grande do Sul. Although it is recorded in various forested areas within its range, the species is found mainly in areas of Araucaria forest (Varty et al., 1994), and to a lesser extent in deciduous and Atlantic forest.

Husbandry protocols for the red-spectacled amazon are the same as for other Amazona species kept at Loro Parque (Sweeney, 1997c). The diet consists of two feeding periods each day. At 7 a.m. the first feed provides the birds with a main food dish containing approx 80 grams of a fruit/vegetable salad which comprises items including apple, orange, carrot, pear, chard, watercress, alfalfa, beetroot, red pepper and papaya. A second, smaller food dish also provides the birds with approximately 30 grams of a commercial pelleted diet (Pretty Bird Hi-Protein Diet). The second feeding period is at 3 p.m., when the birds are given approximately 80 grams of mixed seeds, nuts and cooked beans. Drinking water is available to the birds all day and is supplied in sterilized stainless steel dishes from a purified source which has been passed through a process of chlorination, reverse-osmosis filtration and then finally ultraviolet light sterilisation.

One pair of adult birds are maintained in the exhibition area of the park, while the remaining adult pairs are maintained in suspended breeding cages in the off-exhibit breeding areas. These suspended breeding cages measure 300 cm in length and 98 cm in width and height, and are constructed entirely from wire mesh. The cages are suspended at a base height of about 125 cm above the level of the service pathway, which means that the height of the branching inside the cage is slightly higher than human head height. The front area of the cage, where t food and water is supplied, is covered by a roofing sheet to protect against excessive sunlight, rain, and possible contamination of the food and water by the droppings of the wild birds which live around the breeding area. The entire breeding area is covered by netting to prevent native birds having direct contact with the breeding cages. The cages are positioned with the length of the cage extending away from the pathway at a right angle, with the nest-box at the back, fixed to the outside of the wire, with a hole in the mesh allowing the birds to enter the box. The area surrounding the back of the cages is densely planted and rarely disturbed other than for brief nest-box inspections. The suspended cages are furnished with two main horizontal perches, which extend across the width of the cage, one towards the front and the second towards the back. The birds are not supplied with grit in their diet, but we do include a calcium block hung in the top front corner of every cage (Sweeney, 1997a). It is currently normal practice that the young birds reared each year are placed together at the end of the season in a large aviary (12 m ´ 1.5 m ´ 2.5 m) where they can flock together to improve their social behaviour and allow them flying exercise for at least 12 months prior to their being sexed and having their future location and pairing arrangements decided.

Every cage is cleaned daily, and the exhibition cage is entered so that the floor substrate can be raked. The off-exhibit suspended breeding cages do not need to be entered, instead the floor surface and perches are hosed daily and the substrate below the cage is then raked to remove excrement and dropped food. The cage perching is replaced whenever needed, normally every month due to chewing damage. Additional fresh wood is placed into the cage at least once a week for occupational chewing.

Each bird at Loro Parque is identified individually by a combination of closed leg bands and micro-chips. All red-spectacled amazons reared at Loro Parque have a closed metal leg band placed upon their right leg between 14 and 21 days of age. In addition, at the end of each season after fledging, a micro-chip is implanted into the breast muscle of each young bird reared. A computer record system is maintained which holds individual details of identification, age, health record and breeding history for each bird in the collection.

In addition to the observation of the keeper assigned to each breeding area, all birds are subject to daily observation by either the curator or the assistant curator; any suspicion of illness or poor condition is recorded and then investigated by the staff veterinarians. At the end of each breeding season every bird receives a full routine health examination from the veterinarians, which includes physical examination, weight and appearance records, bacterial cultures, and checking the functioning of the identification micro-chip. If there is concern about the condition of a bird it is transferred into the clinic for closer observation.

Although the red-spectacled amazon has some degree of sexual dimorphism (Forshaw, 1989; Low, 1992), we have found that this is not always a correct guide to gender, particularly in birds less than four years of age. If adult birds seem unable to breed within a three-year period, then checking the sex of the bird by either surgical sexing or blood-sample sexing is recommended.

Pairing procedures for red-spectacled amazons, and other Amazona species at Loro Parque, are being prepared (Sweeney, in prep). Our existing pair arrangements were made by a process of force-pairing, based upon the keeping staff's experience of assessing birds' relative health and physical condition to attain compatibility. This process has been fairly successful, with a total of 24 birds being reared from three different sets of parents over an eight-year period. We believe this level of success can be improved by allowing the birds free mate-choice selection in communal pairing flights (see Sánchez and Waugh, pp. 335–340 above, on a similar experiment with cranes), and we intend to place several of our founder birds, which to date have not demonstrated breeding behaviour, into a communal pairing flight cage in the near future.

Nest-boxes provided for red-spectacled amazons at Loro Parque measure 70 cm in height, by 30 cm in both width and depth. The nesting medium used is exclusively large-sized wood shavings. Each nest box is equipped with an inspection door to allow for easy visual observation of the interior. Inspection is carried out around three times each week when the birds are preparing to breed. Once the first egg has been laid the nest-box is no longer disturbed on a regular basis except to check that the eggs are fertile, normally at around day 10, or if the physical condition of the female appears to be weak without obvious explanation. Once chicks have hatched, the observation checks are again routinely carried out.

The eggs of the red-spectacled amazon are an irregular ovoid shape and white in colour. Measurements of the external dimensions from 16 eggs, laid by four different females, showed mean egg dimensions of 34.3 mm ´ 26.5 mm (Ranges: 32.8/36.0 ´ 23.7/28.9). Clutches of eggs laid at Loro Parque normally range between three and six (mode – four), with fertility of over 90%. Notes from wild nests report that normally two to four chicks are found in each nest (Varty et al., 1994). The incubation period as recorded at Loro Parque is 26 days. Newly hatched chicks commonly weigh from six to ten grams (see Table 3).

The first successful breeding at Loro Parque took place in 1990 when a single offspring was reared; since then a further 24 offspring have been reared during the 1991–1997 breeding seasons.

At Palmitos Park breeding activity was also initiated in 1990 when two birds were reared in the collection. Further breeding took place in 1991 (one chick), 1993 (one chick), 1994 (four chicks), and 1995 (two chicks). The ten offspring produced at Palmitos Park have to date come from five founder bloodlines. Dresden Zoo initiated breeding in 1996 when three offspring were reared from a founder pair. At Vogelpark Walsrode eggs have been laid by two females, but these have, to date, proved to be infertile.

The seasonality of breeding behaviour for red-spectacled amazons in European collections appears to demonstrate a clear breeding season. Figure 1 shows the month of hatching for 32 birds bred in the three successful zoos between 1990 and 1996, with a clear season of hatching from April to late June. Only a single bird hatched just outside of this period in the first week of July.

0040 13/05/1990 0009 0010 Hand-reared

0043 14/05/1991 0009 0010 Hand-reared

0044 14/05/1991 0009 0010 Hand-reared

0045 30/05/1991 0001 0002 Parent

0047 12/05/1992 0009 0010 Hand-reared

0048 17/05/1993 0009 0010 Hand-reared

0051 20/05/1994 0043 0005 Parent

0052 20/05/1994 0043 0005 Parent

0053 20/05/1994 0043 0005 Parent

0059 16/05/1995 0043 0005 Parent

0060 16/05/1995 0043 0005 Parent

0061 16/05/1995 0043 0005 Parent

0062 16/05/1995 0043 0005 Parent

0063 16/05/1995 0043 0005 Parent

0064 16/05/1995 0043 0005 Parent

0065 24/05/1996 0009 0010 Foster

0066 24/05/1996 0044 0040 Parent

0067 24/05/1996 0009 0010 Foster

0068 06/07/1996 0044 0040 Hand-reared

In 1997 six offspring were reared at Loro Parque; all were removed for hand-rearing as the adult birds were being moved to a new breeding centre. The data for Table 3 were collected from the six chicks hand-reared in 1997, plus ESB No. 68, which was hand-reared in 1996.

Management of breeding birds once they are incubating eggs, or brooding chicks, varies from normal husbandry routines by a carefully monitored increase of the food supply and by ensuring that the aviary area receives the minimum possible disturbance. From the date when it has been calculated that the first egg is due to hatch, closer observation of the nest-box interior takes place. Chicks are monitored to ensure that they have good physical development, that they are not being affected by parasites, that there are no signs of parental aggression and that they are being fed correctly by the parents. We have noted on two separate occasions that if the nest-box contains more than four chicks, the potential for aggression is increased. My personal opinion, based upon watching the development of such broods, is that the ideal brood size for parent-rearing in captivity is two to four chicks, and that any additional chicks should be removed for foster-parenting or hand-rearing.

Artificial incubation parameters for eggs of the red-spectacled amazon at Loro Parque are similar to those of most other psittacines (Harvey,

1990: Jordan, 1989). Incubation temperature is maintained at 37.4° C from the initiation of incubation until the time of internal pipping (24–25 days after the initiation of incubation, when the chick's beak first breaks through into the air cell), from which point the temperature is lowered and maintained at 36.6° C. Humidity is maintained at 55% for the incubation period, until it is raised to 90% or higher (the maximum possible level within the incubator) once internal pip (or external pip) has been observed. If eggs are being incubated from an early stage, or if candling of the egg indicates an abnormal size of the air cell relative to the stage of embryo development, closer management of egg weight loss can be implemented (Harvey, 1990; Jordan, 1989). From the beginning of the incubation period until internal pipping has been observed, the eggs should be turned several times a day through 180 degrees, always in alternate directions at each turning. Once pipping has taken place the eggs should no longer be turned. When the egg has pipped and is maintained as described above under hatching conditions, emergence from the egg normally takes place within 48 hours after the first external pip mark has been recorded.

Once hatched, chicks are left undisturbed in the hatcher for up to twelve hours so that they can dry. They are then moved to a brooding incubator, where they are initially maintained at 36.0° C for the first five days; the temperature is then slowly lowered by about one degree every three days, although this change is also dependent upon the chicks' reaction – physical signs that the temperature is too high are panting and a brighter, more reddish skin coloration, while signs that it is too low are lethargy and paler than normal skin coloration. During their early development the chicks are housed singly in stainless steel bowls, which are easy to sterilise. The interior of the bowl is padded with paper towels, which are changed at every feeding period, the towelling being shaped to support the chick's body posture. From the second week onwards, clean wood shavings are used instead of paper towels. The first food is normally given around 12 hours after hatching, although this can vary according to the chick's condition after hatching and the amount of yolk sac which is still visible through the skin as being unabsorbed. The first food given is simply a lactated ringers solution with a psittacine-specific strain of lactobacillus added. If the chick appears dehydrated, the following feeds of the first day can also consist mainly of lactated ringers solution to hydrate the chick. If its condition is normal, from the second feed onwards the chick receives a commercial hand-rearing diet (manufactured by Pretty Bird International) throughout its development until weaning. The preparation and dilution of the diet is shown in Table 2.

Table 2. Food preparation and feeding frequency guidelines for Amazona pretrei.

1 10% 10

2 12% 10

3 15% 10

4 18% 10

5 20% 10

6 23% 8

7–13 25% 7–8

14–20 25% 7

21–27 25% 6

28–34 25% 5

35–41 25% 3–4

42–48 25% 2

49–55 25% 1–2

This commercial diet is available with different levels of fat. We generally use a 12% fat level for hand-rearing Amazona species, but take care that the chicks do not show signs of being over-weight in the later stages of development, from the time when they become covered with pin-feathers through until weaning. If a chick is considered to be over-weight for its stage of development (assessed by the presence of an excessive fat layer on the breast), we change it for the remainder of its rearing period to an 8% level of fat in a diet which is otherwise the same. The food is always prepared for the chick at a temperature of 40° C, although it may cool slightly during the feeding process. The preferred instrument for feeding is a shaped teaspoon during the first two weeks, after which a syringe is used, because it is capable of holding a greater quantity of food without the need to be repeatedly returned to the food source (risking cross-contamination between chicks). The nursery at Loro Parque is staffed from 6.00 a.m. until midnight every day, and the chicks are generally fed throughout this 18-hour period at regular intervals dependent on the number of feeds currently being given (see Table 2). The progress of the chick's development is monitored by observations of its physical condition and daily records of its weight. All measurements of weight are taken at 6.00 a.m., when the chick's crop is empty prior to the first food of the day being given. A guide to the expected pattern of weight gain is provided by the data in Table 3.

Weaning parameters for the red-spectacled amazon do not vary from those described for other Amazona species (Low, 1985; Schubot et al., 1992; Stoodley, 1990; Sweeney, 1997c). We always try to accommodate more than one amazon parrot together during weaning, as peer interaction greatly speeds up the weaning process. Human contact is kept to a minimum and the chicks are supplied with large pieces of food which can easily be held in the foot. These food items are placed at perch height within easy reach of the birds, and items such as various fruits, carrot, corn-on-the-cob, and large-sized weaning pellets (manufactured by Pretty Bird) are given in addition to a food dish of the sort normally used for adult amazon parrots.

The red-spectacled amazon has always been a rarely-seen bird in European zoological collections. When a survey was carried out in the four collections in the European region that maintain the species, this showed that on 31 December 1996 there was a living population of 61 birds with a near even sex ratio (25.27.9), existed and that three of the four collections were achieving successful breeding. At least two private keepers in Europe are known to maintain the species in small numbers, but so far they have not participated in joint management initiatives.

An analysis of the genetic status of the population in European zoos (Sweeney, 1997b) shows that the living population has 30 founder birds, of which nine are contributors and 21 have the potential to contribute. One additional founder bird which has now died did produce four offspring which are living and have the potential to reproduce. The remainder of the living population consists of 25 first-generation birds (bred from ten founder bloodlines), four birds which are the result of a first-generation male breeding with a founder female, and two second-generation birds bred from a sibling pair of first-generation birds. Steps have now been taken to reduce any further inbreeding, and exchanges of first-generation birds are taking place between the four institutions currently working with the species, to allow unrelated first-generation pairs to be formed.

Given that the population is now growing and that the species is threatened in its wild state, the red-spectacled amazon has been included in a list of Amazona species to be subject to European zoo collection

Hatch 6.6 7.9 8.2 8.6 9.2 8.3 9.9 8.4 1.04 0.38

1 7.6 8.2 8.5 8.6 9.2 8.8 10.8 8.8 1.01 0.38

2 8.7 9.2 9.3 9.2 10.3 10.9 11.4 9.9 1.01 0.38

3 9.9 10.5 10.1 10.1 11.1 11.7 12.5 10.8 0.97 0.37

4 11.8 11.9 11.2 11.3 12.6 13.0 14.8 12.4 1.25 0.47

5 13.8 13.7 12.9 13.2 14.8 14.9 16.1 14.2 1.12 0.42

6 15.4 16.4 14.4 15.0 17.1 17.5 18.0 16.3 1.36 0.51

7 17.7 18.5 16.5 18.2 19.2 20.6 20.7 18.8 1.53 0.58

8 20.3 20.8 19.4 21.6 21.2 23.9 24.0 21.6 1.75 0.66

9 24.8 23.8 21.2 24.8 23.9 27.1 29.6 25.0 2.67 1.01

10 28.3 27.0 24.9 26.4 27.8 32.0 33.8 28.6 3.17 1.20

11 32.9 31.2 28.7 29.5 31.9 36.3 38.4 32.7 3.53 1.33

12 38.2 37.3 33.1 33.9 37.0 43.1 46.8 38.5 4.90 1.85

13 44.5 44.9 39.0 40.0 45.3 46.0 45.6 43.6 5.40 2.04

14 52.2 52.6 47.9 48.5 51.0 54.6 67.4 53.4 6.58 2.49

15 59.7 61.6 56.1 56.7 64.9 65.0 80.0 63.4 8.19 3.10

16 68.9 73.9 74.0 69.3 73.4 76.0 90.0 75.0 7.08 2.68

17 81.5 87.6 81.4 80.1 92.2 91.6 111.0 89.3 10.77 4.07

18 88.0 101.0 90.9 94.3 104.0 110.0 120.0 101.2 11.30 4.27

19 103.0 116.0 103.0 99.2 120.0 123.0 130.0 113.5 11.80 4.46

20 120.0 131.0 117.0 104.0 135.0 137.0 148.0 127.4 14.70 5.56

21 138.0 147.0 128.0 118.0 148.0 158.0 163.0 142.9 16.03 6.06

22 155.0 160.0 140.0 133.0 169.0 165.0 177.0 157.0 15.74 5.95

23 171.0 180.0 144.0 149.0 177.0 171.0 192.0 169.1 17.06 6.45

24 183.0 198.0 169.0 162.0 191.0 191.0 198.0 184.6 14.13 5.34

25 197.0 211.0 182.0 177.0 206.0 209.0 218.0 200.0 15.40 5.82

26 210.0 223.0 196.0 189.0 216.0 220.0 226.0 211.4 14.05 5.31

27 217.0 238.0 206.0 202.0 228.0 238.0 236.0 223.6 15.32 5.79

28 223.0 257.0 218.0 214.0 245.0 247.0 239.0 234.7 16.42 6.21

29 236.0 266.0 231.0 224.0 250.0 258.0 248.0 244.7 15.06 5.69

30 247.0 269.0 243.0 238.0 256.0 259.0 252.0 252.0 10.46 3.95

31 255.0 276.0 254.0 247.0 268.0 263.0 262.0 260.7 9.66 3.65

32 263.0 291.0 265.0 256.0 268.0 272.0 265.0 268.6 11.03 4.17

33 269.0 296.0 271.0 260.0 273.0 277.0 284.0 275.7 11.57 4.37

34 273.0 297.0 278.0 266.0 284.0 281.0 288.0 281.0 10.09 3.81

35 285.0 309.0 282.0 267.0 284.0 287.0 292.0 286.6 12.55 4.74

36 290.0 314.0 288.0 277.0 289.0 291.0 294.0 291.9 11.13 4.21

37 298.0 315.0 292.0 280.0 291.0 290.0 297.0 294.7 10.70 4.04

38 311.0 317.0 298.0 282.0 293.0 292,0 299.0 298.9 11.85 4.48

39 314.0 321.0 299.0 287.0 297.0 291.0 300.0 301.3 12.15 4.59

40 315.0 320.0 304.0 286.0 297.0 299.0 311.0 304.6 11.70 4.42

41 318.0 322.0 308.0 288.0 309.0 295.0 312.0 307.4 12.10 4.57

42 319.0 320.0 304.0 291.0 307.0 300.0 318.0 308.4 11.05 4.18

planning. In addition, a petition was presented in 1996 by Loro Parque for the forming of a European Regional Studbook, and this was approved by the EEP committee of EAZA in 1997 (Sweeney, 1997b).

Dresden Zoo 2 1 3

Loro Parque 10 11 5

Palmitos Park 11 13 1

Vogelpark Walsrode 2 2 0

Total 25 27 9

The first captive breeding of the red-spectacled amazon was recorded in 1990, when two collections reared the species successfully. In the six following years more than 30 young have been reared and the captive population in European zoos has doubled (Sweeney, 1997c). With the creation of a regional studbook much greater attention can be given to the movement and pairing of the first-generation birds already reared within the population, to avoid the risk of inbreeding (Sweeney, 1997b). Concentrated effort is also being focused upon stimulating reproduction from the 21 founders who still have the potential to contribute. The age distribution is very healthy, as half the birds are less than seven years old and so far the population has shown an even sex ratio. Fieldwork on the wild population still continues; the results of an intensive two-year survey estimate a remaining wild population of between 7,500 and 8,500 birds (Varty et al., 1994), and the authors of the survey report feel that the most pressing conservation need is to further secure some of the key regions of the species' range from the threat of habitat disturbance.

Hi-protein select pellets and hand-feeding diet. Pretty Bird International Inc., P.O. Box 177, Stacy, Minnesota 55079, U.S.A.

Lactated ringers solution. B. Braun Medical S.A., Crta. de Terressa 121, 08191 Rubi (Barcelona), Spain.

Roger G. Sweeney was until recently Curator of Birds at Loro Parque, Puerto de la Cruz, Tenerife, Spain. He may now be contacted at: Dymocks Mill Cottage, Oldcastle, Malpas, Cheshire SY14 7NE, U.K.