News on the captive
management of the Lear’s Macaw
by
David Waugh and Matthias Reinschmidt
Loro Parque
Fundación
The
Lear´s Macaw Anodorhynchus leari,
a CITES Appendix 1 species endemic to north-east Brazil, is designated as
Critically Endangered (IUCN Red List category – www.birdlife.org) because it
has an extremely small population which breeds and is resident in one area
(3,900 km2). In its semi-arid habitat of the caatinga
it has a close relationship with the licuri palm (Syagrus coronatus),
which produces the hard fruits forming the major part of the macaw’s diet.
Given that licurí palm-stands formerly covered
250,000 km2 but have been vastly reduced by livestock-grazing,
it is threatened by the degradation of its habitat. It further threatened by
illegal trapping for trade (BirdLife International
2000, 2006), and there are occasional shootings of macaws by farmers where
attacks on maize crops occur. The most recent (2006) estimate of the total wild
population is 632 birds.
Actions
for the conservation of the wild population and its habitat have been underway
for a number of years, and a plan has been published recently to clarify and
prioritise the necessary conservation measures (IBAMA 2006). The plan also
includes the use of captive breeding as an ex situ conservation tool for
the species. The Loro Parque
Fundación (LPF) of Tenerife, Spain, together with the
Brazilian Government agency IBAMA (Brazilian Institute of Environment
and Renewable Natural Resources) and other partners, is contributing to the
field conservation project. Furthermore, the LPF Curator, Matthias Reinschmidt is the international studbook keeper with
support from Onildo Marini-Filho
of IBAMA and Ryan Watson of Al Wabra Widlife Preservation. This article presents current
information about the captive population.
Table 1.
Distribution of Lear’s Macaws in the managed population
|
Participating institution |
Country
|
Status*
|
|
Al Wabra
Wildlife Preservation |
Qatar |
4.5.0 |
|
Crax – Wildlife Research Society |
Brazil |
1.1.0 |
|
Harewood Hall |
United Kingdom |
1.2.0 |
|
Loro Parque Fundación |
Spain |
2.2.0 |
|
Lymington Foundation |
Brazil |
2.4.0 |
|
Rio de Janeiro Zoo |
Brazil |
6.5.0 |
|
Sao
Paulo Zoo |
Brazil |
3.5.0 |
|
|
Total: |
19.24.0 |
* (males.females.gender
unknown)
In
the studbook (Reinschmidt
2006) are
seven participating institutions with 43 officially incorporated birds (Table
1). These are the birds which currently form the managed captive population
which is under the coordination of IBAMA, the birds being on deposit from the
Brazilian Government. There is an additional living specimen confiscated by the
competent authorities in Brazil in October 2006, which will be
incorporated into the managed population.
There are a further two female living specimens also likely to join the
official population. There are an undisclosed number of Lear’s Macaws in
Switzerland, for which there is no definite prospect of their inclusion in the
officially managed population.
Demographically
the managed population requires a breeding momentum to add more young birds, as
can be seen from the age pyramid (Figure 1), and improvement of the current sex
ratio of 0.74, by the addition of more males. However, the breeding programme
is necessarily at an early stage. Because most of the macaws have been
recruited to the population as confiscated young birds taken in their first
year of life, there are close estimates of the ages, even though they are
registered in the studbook as wild-caught. Furthermore, endoscopic
examination of the condition and stage of development of the gonads of these
birds reveal that at 7 to 8 years of age they are only just entering
reproductive maturity (L. Crosta and L. Timossi, in litt.). This
coincides well with the first studbook registered breeding occurring in 2006 at
Al Wabra Wildlife Preservation in Qatar, which holds
the oldest birds.
Figure 1. Age pyramid of the managed population of Lear’s Macaws.
Given that 42 of the studbook registered macaws are wild-caught, founders apparently constitute 97.6% of the captive population, a remarkable and positive situation. However, given that these macaws have been taken from nests, and often were confiscated together, there is a reasonable probability that the founders (which by definition should be unrelated) include siblings. However,
despite this possibility, the
genetic situation overall in the Lear’s Macaw studbook is favourable, as can be
demonstrated by work in progress of Prof. Cristina Miyaki
and her team at the Institute of Molecular Genetics, University of Sao Paulo.
Dr Miyaki has carried out DNA analysis from blood
samples obtained from these macaws, and has been able to calculate a genetic
similarity index between all of the individuals. Thus she has all
possible pairings ranked according to the statistical probability of genetic
relatedness of the birds (in five ranks, from lowest relatedness = A, to
highest = E).
In general terms (scientific details, Miyaki et al., in prep.) this indicates the
following. The macaws sampled (17.21) have a total of 357 pairing combinations,
which show 115 (32.2%) in the low relatedness categories (A,B), 131 (36.7%) in
the medium category (C) , and 111 (31.1%) in the high categories (D,E).
Currently, all 17 males with known similarity indices are paired with females,
with relative proportions of genetic relatedness as shown in table 2. The same
table indicates the changes in these proportions if re-pairing of macaws takes
place within each institution, i.e. before interchange of macaws between institutions.
The pairings according to institution are shown in table 3.
Table 2. Pairings of Lear’s Macaws in the managed
population: level of genetic relatedness currently and after re-pairing within
each institution.
|
Level
of relatedness |
Current
pairings |
Re-pairings
|
|
|
No. |
% |
No. |
% |
|
Low (A,
B) |
5 |
29.4 |
11 |
64.7 |
|
Medium
(C) |
3 |
17.7 |
5 |
29.4 |
|
High
(D,E) |
9 |
52.9 |
1 |
5.9 |
|
Total |
17 |
100.0 |
17 |
100.0 |
Table 3.
Level of relatedness in possible re-pairings of Lear’s Macaws within each institution.
|
Participating institution |
Relatedness
of pairings |
|
Al Wabra
Wildlife Preservation |
1A, 1B, 2C |
|
Crax – Wildlife Research Society |
1E |
|
Harewood Hall |
N/A |
|
Loro Parque Fundación |
1B, 1C |
|
Lymington Foundation |
1A, 1C or 2B |
|
Rio de Janeiro Zoo |
4A, 1C |
|
Sao
Paulo Zoo |
3A |
Given that in the first instance it is
easier to manage species populations on a regional basis, it would make sense
to exchange birds for further re-pairings between the holding institutions in
Brazil. From the 11.15 captive Lear’s Macaws currently in Brazil, it is
possible to make 11 low-relatedness (A) pairings. Any intention to re-pair
these birds must take into account the compatibility of the individuals within
pairs, revealed primarily by their behaviour, and following precautions:
1. For birds not in successfully reproducing pairs, give the possibility for free mate choice in flocks. However, before breaking non-reproducing pairs, take age into consideration.
2.
Aim for most genetically acceptable pairings, but before breaking existing pairs take breeding history and age into consideration.
Acknowledgements
We thank Prof. Cristina Miyaki for making available the rankings of relatedness of possible pairings.
References
BirdLife International (2000) Threatened
birds of the world. Barcelona and Cambridge, UK: Lynx Editions and BirdLife International
BirdLife International (2006) Species factsheet: Anodorhynchus leari.
Downloaded from http://www.birdlife.org on 7/12/2006
IBAMA
(2006) Management Plan for the Lear’s Macaw (Anodorhynchus leari). Endangered Species Series 4. Brasilia: Brazilian
Institute of Environment and Renewable Natural Resources, Fauna Species
Protection Coordination.
Reinschmidt, M (2006) Lear’s
Macaw (Anodorhynchus leari) International
Studbook, Annual Report and Recommendations for 2006. Puerto de la Cruz, Tenerife: Loro Parque Fundación.
Foto: Matthias
Reinschmidt/Loro Parque Fundación