Timing of Birth, Female Reproductive Success and Infant Sex Ratio in Semifree-Ranging Barbary Macaques (Macaca sylvanus).

Folia Primatologica 42 (1): 2-16. ISSN: 0015-5713 (Print); eISSN: 1421-9980 (Online).

Arbeit durchgeführt im Affenberg Salem.

Abstract:

Examined were 5 years of data on the reproduction of a semifree-ranging population of Barbary macaques (Macaca sylvanus). In this seasonally breeding species – birth season: mid-March to beginning of August – primiparous 4-year-old females gave birth significantly later in the year than older primiparous and multiparous females, respectively. Multiparous females without an infant from the preceding season gave birth significantly earlier than females who had raised an infant. 88.4% of birth intervals were approximately 1 year, 11.6% about 2 years. Infant loss did not influence the length of the interbirth interval, but after the birth of the next surviving infant the interval was significantly longer. The interval following the 1st infant was significantly longer than after subsequent infants. After the birth of daughters primiparous females had markedly longer birth intervals than after the birth of sons. Infant mortality was 9.1%. Neonatal mortality was influenced by rank and parity of the mother and sex of the infant. Allomothering and aggression by older group members are thought to be the main causes of infant mortality. Female reproduction rates were not dependent on rank. High-ranking females, however, bore their 1st infant significantly earlier than low-ranking females. Low-ranking females had more daughters than sons, in high-ranking females the reverse was found. Differences from findings of other species are discussed with regard to differences in social organization and the reproductive strategies resulting from them.

paul-biblio

Breeding Biology of Vanellus chilensis (AVES: Charadriidae) in a Peri-urban Area of Southern Brazil.

Revista de Ciéncia Ambientais 13(3): (ISSN 1981-8858). http://dx.doi.org/10.18316/rca.v13i.6070

Abstract:

The neotropical species Vanellus chilensis, known as Southern Lapwing, is found in grassland environments, in rural and urban open areas. e species is considered a social Bird, which aggregates in pairs or small groups during the breeding period, in austral spring and summer. During the reproductive period, the cooperative breeding behavior is common among individuals of the species, when a non-breeding individual, called "helper", assists the breeding pair in parental care activities. We monitored a total of 11 social breeding unities of V. chilensis between august 2014 and january 2015 in the Universidade do Vale do Rio dos Sinos campus, in São Leopoldo, Rio Grande do Sul. We conducted nest observations, by evaluating the breeding success of individuals regarding eggs and chick's loss, with and without helpers' presence, as well as behavioral aspects. We recorded the laying of 65 eggs, of which 10.7% achieved breeding success, regarding the number of viable chicks. In this study, helpers' presence in the nests did not influence the breeding success of individuals, thus, dismissing the hypothesis that helpers' assistance improves breeding success of the species. Our findings contribute to the knowledge on the breeding biology of V. chilensis in peri-urban areas.

haeberlin-biblio

An Initial Study of the Effects of Hand Rearing on the Future Reproductive Success of Female Captive Felids.

Research Dissertation

61 Seiten

Edinburgh Napier University
Masters of Wildlife Biology and Conservation, Dr. Jason Gilchrist
Zoo Salzburg

Abstract:

This project aimed to assess the future reproductive effects of hand- rearing female felids, compared to their maternal-reared counterparts. Both the future success of the cubs, and the subsequent success of dams that have cubs removed from them, were analysed.

Studbook data of various felid species and subspecies were analysed, including the Amur leopard (Panthera pardus ssp orientalis), Amur tiger (Panthera tigris ssp altaica), Sumatran tiger (Panthera tigris ssp sumatrae), Sandcat (Felis margarita), Asian golden cat (Catopuma temminckii), Ocelot (Leopardus pardalis) and Rusty-spotted cat (Prionailurus rubiginosus). A total of 4569 felids, 356 of them hand- reared, were assessed. A small volume of additional qualitative data was obtained from questionnaires of institutions breeding big cats.

Results supported predicted hypotheses and anecdotal concerns. Hand- reared mothers showed a lower likelihood of successfully rearing at least one cub (Chi2= 11.807, df = 2, p = 0.012), a lower average number of successful offspring (one-way ANOVA, F = 4.32, df = 1, p = 0.038), and a lower average reproductive score on a scaled system (one-way ANOVA, F = 3.89, df = 1, p = 0.049). Hand- reared mothers also show a higher probability of having all of their cubs hand- reared (Chi2 = 11.724, df = 1, p = 0.001), though when cumulated with mothers that require only some cubs hand- reared, results becomes marginally insignificant (Chi2 = 3.261, df = 1, p = 0.071).

The results also indicate a lower average probability of success of subsequent cubs in mothers who have their first cub removed and hand-reared, compared to mothers whose first cub was allowed to perish in their care (two-sample t-test, t = -9.42, df = 58, p = 0.000). Despite limited qualitative data availability and the resulting inevitable weaknesses in power of the results, the project does demonstrate a statistically significantly lower reproductive success rate in hand-reared cats compared to their maternal- reared counterparts, as well as a reduced subsequent success rate for mothers who have cubs hand-reared.

With these results in mind, the project recommends caution when electing to hand-rear felid cubs, even in the event of negligent dams. However, significant further testing is recommended, particularly in relation to the circumstances of removal of cubs from their mother. In addition, a larger sample size of fostered cubs would enable an evaluation of the genetic versus behavioural predisposition to poor maternal success.

moore-biblio