Article

Reproductive biology and behavior of captive female Matschie's tree kangaroos, Dendrolagus matschiei

Authors:
To read the full-text of this research, you can request a copy directly from the author.

Abstract

Thesis (Ph. D.)--University of Washington, 1994 All species of tree kangaroos (Dendrolagus spp.) are considered vulnerable or threatened in the wild. Their numbers have been reported to be adversely affected by hunting and habitat destruction in Australia and New Guinea (Martin 1992, Hutchins & Smith 1990, Kennedy 1986, Pernetta & Hill 1986). In captivity, breeding has not sustained viable populations for most species and the reproductive rates of all species are below their potential (Steenberg & Smith 1990). One reason for problems in captive management is a lack of knowledge about Dendrolagus reproductive biology. This genus differs morphologically and behaviorally from the more well known terrestrial kangaroo species.The present study documented both the physiological and behavioral aspects of estrous cycles of captive Dendrolagus matschiei females. The estrous cycle-length data based on steroid hormones were obtained from radioimmunoassay measurements of estrogen and progestin concentrations from fecal samples. This was the first quantitative fecal steroid analysis study on a marsupial species. Behavioral correlates of estrus were measured through focal animal observations. From both of these data sets, hypotheses were tested addressing how this genus fits into the general pattern of marsupial reproduction.The mean ($\pm$ one standard deviation) length of the estrous cycles for captive D. matschiei was 56.83 $\pm$ 3.12 days (n = 6) based on fecal estrogen profiles and 54.17 $\pm$ 5.74 (n = 6) based on fecal progestin profiles. For two of the females, reproductive behaviors occurred at approximately the calculated time of estrus, giving further support to the duration of estrous cycles. Several behavioral indicators of estrus were documented. Two other general patterns emerged from the hormone profiles of the female D. matschiei: (1) A spike of estrogen around the time of ovulation and (2) a rise in progestin after the estrogen peak.D. matschiei seems to have a similar reproductive cycle with several notable differences to those of other known macropodids. The D. matschiei estrous cycle is longer than all other known macropod cycles by at least 10 days. The gestation length of 44.2 days for D. matschiei (Heath et al. 1990) is also longer than any other known macropodid species by at least 6 days. Life history data obtained from captive tree kangaroo historical records showed that D. matschiei has an extended age of female sexual maturity which is later than other macropodids, and that D. matschiei has a reduced fecundity rate. The reason for these differences could be based on D. matschiei's ecological niche. It is an arboreal folivore with a relatively low metabolic rate (McNab 1978) which could result in an overall slower reproductive output.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the author.

... In der Unterklasse der Beuteltiere gibt es eine Vielzahl unterschiedlicher Längen reproduktiver Zyklen. Bradshaw and Bradshaw (2011) (Bradshaw & Bradshaw, 2011) und dem Matschie-Baumkänguru (Dendrolagus matschiei) mit 56-60 Tagen (North & Harder, 2008), 55-61 Tagen (Dabek, 1994), 56-57 Tagen (Franke, 1995) und 63 Tagen (Flannery et al., 1996) (Bradshaw & Bradshaw, 2011). Demnach besitzen Baumkängurus nicht nur innerhalb der Familie der Macropodidae, sondern auch in der Unterklasse der Beuteltiere die längste Zykluslänge. ...
... Demnach ist es wünschenswert, den Eisprung oder den Übergang von Luteal-zu Follikelphase an Verhaltensparametern zu erkennen. Dabek (1994) kam in ihrer Studie über Matschie-Baumkängurus zu dem Schluss, dass es im Gegensatz zu vielen anderen Säugetierarten, die eine Vielzahl von Verhaltensweisen zur Zeit des Eisprunges zeigen, bei Matschie-Baumkängurus keine Verhaltensweisen der Weibchen unter Gehegebedingungen gibt, die mit einem Eisprung in Verbindung gebracht werden können. Allerdings führt sie auf, dass die Männchen innerhalb der Eisprungphase der Weibchen eine erhöhte Aktivität und Aggression zeigten. ...
... Dabei konnten sich die Tiere allerdings nicht sehen, da es sich um eine durchgängige Trennwand ohne Zwischengitter handelte. Dies bestätigt die von Dabek (1994) aufgestellte Vermutung, dass die männlichen Tiere auf Gerüche reagieren, welche das weibliche Tier bei erhöhten Östrogenwerten freisetzt. ...
Article
Full-text available
Currently seven animal species worldwide are managed in Global Species Management Programs (GSMPs). Since 2013 the Goodfellow's tree kangaroo (Dendrolagus goodfellowi) is the first marsupial in this group of species. The primary goal of the GSMP is to enhance the sustainability of the captive population. Reproductive cycles of seven female Goodfellow-tree kangaroo's kept in German zoos were studied during a period of 23 weeks. Faecal samples and behavioural data were collected in order to identify oestrous specific behaviour. Faecal hormone metabolites were analysed using an enzyme-immunoassay for 4-Pregnen-20α-ol-3-one (trivial name: 20α-Progesterone). Faecal hormone metabolites indicated reproductive activity in all females studied, even in a 19 year old individual. The average oestrous cycle was 54.3 ± 1.6 days. During oestrus periods females showed significantly more pouch licking behaviour (p < 0,01), while the breeding male had significantly more interest in females (p < 0,05) indicated by sniffling and vocalization (sound: clicking/“chitching”). Finally this study demonstrates that the applicability of faecal hormone analysis is an adequate method for reproductive monitoring in Goodfellow's tree kangaroos.
... Instead the tree kangaroo reproductive cycle seems to be more reflective of the groups low metabolic rate strategy. Matschie's tree kangaroos have an oestrous cycle of 54-55 days, approximately two lunar months, one of the longest of any marsupial (Dabek, 1994). ...
... Female tree kangaroos reach sexual maturity at three years of age, males at approximately two years. (Dabek, 1994;Flannery et al., 1996;Strahan, 1995). ...
Thesis
p>Tree kangaroos (Marsupialia: Macropodidae, Dendrolagus) are some of the Australasian region's least known mammals. Basic questions concerning the population and conservation status of many species remain unanswered. However, there is sufficient anecdotal evidence of population decline and local extinctions to designate tree kangaroos as New Guinea's most endangered mammal group. Tree kangaroo dung was sampled at four sites in Papua New Guinea (PNG). Distance sampling andysis was used to estimate tree kangaroo dung pellet densities for two of these sites. Pooled results for three trials at these sites give estimates of 51.2 - 109.8 pellets/ha for Matschie's tree kangaroo {Dendrolagus matschiei). Captive defecation rates for D. matschiei and three other tree kangaroo species were determined. Using this rate as well as a measured average pellet alteration time of approximately three days gave animal density estimates of 0.6-1.4 animals/hectare for the three trials. The precision of the density estimates is affected by uncertainties in the identification of tree kangaroo dung, by the equivalency of captive versus wild pellet production rates, and in the rate and constancy of dung decomposition. Possible solutions for these problems are discussed. The results indicate that distance sampling analysis of dung pellet counts shows promise at colder, higher altitude sites in New Guinea but may not be appropriate for hotter, lower elevation areas with high coprophagous arthropod populations. Tree kangaroo food plants were documented. Food plants for Matschie's (D. matschiei). Dona's {Dendrolagus dorianus), and Goodfellow's {Dendrolagus goodfellowi) tree kangaroos were collected at two sites with the aid of landowners, and later identified by botanists in Papua New Guinea and Australia. The collections support Australian data that tree kangaroos are browsers, with the largest proportion of their diet coming from leaves and shoots from a wide variety of plants from at least 40 families for Matschie's, and 33 families for Goodfellow's and Doria's. Landowners from different areas of the country were in agreement that tree kangaroos favour eating leaves and stems of plants, with fruits and flowers comprising a relatively minor proportion of the animals' diets. Additional information on tree kangaroo biology and conservation status was obtained through the use of formal and informal landowner interviews. Interview methodology was insufficient to produce many quantifiable results, but did give novel insights into tree kangaroo natural history, distribution, conservation status, and human utilisation. The interviewee responses indicate that the conservation status of the Matschie's tree kangaroo, D. matschiei, is perceived to have declined in recent decades, but this decline is not uniform. The current economic downturn in PNG may be encouraging overhunting in some areas as villagers search for ways to supplement their incomes. However, in other areas tree kangaroo numbers may be stable or increasing due to sociocultural and economic changes that have led to a decline in hunting intensity.</p
... At the NZP-CRC, she worked with Larry Collins who had done leading research on gestation and reproduction on the NZP-CRC's colony of 20 Matschie's tree kangaroos (Olds and Collins, 1973). Her work in the reproductive endocrinology laboratory of Dr. Samuel Wasser established reproductive cycles through non-invasive hormone collection from dung (Dabek, 1994;Chapter 21). As part of her research, Dabek learned that the Matschie's tree kangaroo was considered endangered, and few studies had been done in the wild. ...
Chapter
Tree kangaroo populations face numerous threats in the wild due to anthropogenic factors including loss of habitat and hunting pressures, as well as natural catastrophes brought on by the effects of climate change (e.g., drought, wildfires). The global conservation community has been working together to ensure a future for these threatened species in a One Plan Approach calling for collaboration between ex situ and in situ forces. Conservation strategies with the goal of maintaining long-term viable tree kangaroo populations in healthy ecosystems incorporate a transdisciplinary process involving local communities in range countries working with an international set of wildlife researchers and caretakers supported by zoos across the world. Zoological institutions contribute to conservation of tree kangaroo species and ecosystems on many levels. Global and regional zoo associations scientifically maintain their tree kangaroo populations to retain genetic diversity, demographic stability, and behavioral integrity. Researchers in both ex situ and in situ programs share information on biology, physiology, and ecology to the benefit of both. Tree kangaroos in accredited zoos have a conservation role as ambassadors to raise awareness and engage visitors to care about conservation status in the wild. Finally, zoos generate considerable funding to support overall One Plan Approach conservation strategies. Only through the global collaboration of ex situ and in situ conservation communities, will the future be ensured for tree kangaroo species in their natural habitats.
Article
Matschie's tree kangaroo (Dendrolagus matschiei) is an endangered species that has been bred in captivity since the 1970s. In 1992, the Tree Kangaroo Species Survival Plan(®) (TKSSP) was established to coordinate the captive management of Association of Zoos and Aquariums (AZA) D. matschiei. The TKSSP makes annual breeding recommendations primarily based on the mean kinship (MK) strategy. Captive breeding programs often use the MK strategy to preserve genetic diversity in small populations-to avoid the negative consequences of inbreeding and retain their adaptive potential. The ability of a captive breeding program to retain the population's genetic diversity over time can be evaluated by comparing the genetic diversity of the captive population to wild populations. We analyzed DNA extracted from blood and fecal samples from AZA (n = 71), captive (n = 28), and wild (n = 22) D. matschiei using eight microsatellite markers and sequenced the partial mitochondrial DNA control region gene. AZA D. matschiei had a similar expected heterozygosity (H(e) = 0.595 ± 0.184) compared with wild D. matschiei (H(e) = 0.628 ± 0.143), but they had different allelic frequencies (F(ST) = 0.126; P < 0.001). AZA D. matschiei haplotype diversity was almost two times lower than wild D. matschiei Ĥ = 0.740 ± 0.063. These data will assist management of AZA D. matschiei and serve as a baseline for AZA and wild D. matschiei genetic diversity values that could be used to monitor future changes in their genetic diversity.
Article
The Association of Zoos and Aquariums (AZA) Matschie's tree kangaroo (Dendrolagus matschiei) population is at a critical point for assessing long-term viability. This population, established from 19 genetically uncharacterized D. matschiei, has endured a founder effect because only four individuals contributed the majority of offspring. The highly variable mitochondrial DNA (mtDNA) control region was sequenced for five of the female-founders by examining extant representatives of their maternal lineage and compared with wild (n = 13) and captive (n = 18) D. matschiei from Papua New Guinea (PNG). AZA female-founder D. matschiei control region haplotype diversity was low, compared with captive D. matschiei held in PNG. AZA D. matschiei have only two control region haplotypes because four out of five AZA female-founder D. matschiei had an identical sequence. Both AZA haplotypes were identified among the 17 wild and captive D. matschiei haplotypes from PNG. Genomic DNA extracted from wild D. matschiei fecal samples was a reliable source of mtDNA that could be used for a larger scale study. We recommend a nuclear DNA genetic analysis to more fully characterize AZA D. matschiei genetic diversity and to assist their Species Survival Plan((R)). An improved understanding of D. matschiei genetics will contribute substantially to the conservation of these unique animals both in captivity and the wild.
Article
The population of Matschie's tree kangaroos (Dendrolagus matschiei) held in North American zoos has declined to critically low numbers, and information on the reproductive biology of tree kangaroos is limited. The objectives of this study were to (1) characterize the temporal features of the estrous cycle through the measurement of fecal progesterone metabolite (i.e., progestin) concentrations and (2) determine the reproductive status of female tree kangaroos in the captive population of North America through the identification of estrous cyclicity. Fecal pellets and observations of estrous behaviors were collected from 16 captive female tree kangaroos. Fecal pellets were sampled and extracted with methanol, and progestin concentrations were quantified using a radioimmunoassay (RIA) for progesterone and its metabolites. A progestin profile was obtained for each female by plotting fecal progestin concentrations for every third day over a 120-day period. Profiles for 12 of 16 females showed evidence of estrous cyclicity (P<0.01). The mean length of the estrous cycle was estimated at 58.9+/-2.4 days (n=11). Progestin concentrations were low during the first 15-20 days of the luteal phase and remained elevated above baseline only during the last 30.2+/-3.2 days of the luteal phase, which averaged 46.6+/-2.5 days in duration. The progestin profile observed in the estrous cycle of Matschie's tree kangaroos in this study is very similar to that seen in the non-pregnant cycle of several other species in the family Macropodidae.
ResearchGate has not been able to resolve any references for this publication.