National Zoological Park's Conservation Research Articles

A New Species of Scimitar-Babbler (Timaliidae: Jabouilleia) From the Sub-Himalayan Region of Myanmar

Abstract An expedition of representatives from the Myanmar Nature and Wildlife Conservation Division and the Smithsonian National Zoological Park's Conservation and Research Center visited the town of Naung Mung on the Nam Tisang River in the extreme northern portion of Kachin State, Myanmar, during February 2004. The town is located in the sub-Himalayan region of the country at 27°29′N, 97°48′E, elevation 540 m, 118 km south of the Tibetan border and 53 km west of the border with Yunnan Province, China. The purpose of the trip was to inventory the poorly known avifauna of the premontane temperate rainforest habitat at that site. On 6 February 2004, we captured two scimitar-babblers that appeared to be representatives of the genus Jabouilleia. An additional individual of the taxon was captured in the same vicinity on 8 February 2004. These were the first records for Jabouilleia from Myanmar, and subsequent investigation showed that these specimens were members of a previously undescribed species, which we designate Jabouilleia naungmungensis, the Naung Mung Scimitar-Babbler. Une Nouvelle Espèce de Jabouilleia (Timaliidae) dans la Région sub-Himalayenne de la Birmanie

A NEW SPECIES OF SCIMITAR-BABBLER (TIMALIIDAE: JABOUILLEIA) FROM THE SUB-HIMALAYAN REGION OF MYANMAR

Abstract An expedition of representatives from the Myanmar Nature and Wildlife Conservation Division and the Smithsonian National Zoological Park's Conservation and Research Center visited the town of Naung Mung on the Nam Tisang River in the extreme northern portion of Kachin State, Myanmar, during February 2004. The town is located in the sub-Himalayan region of the country at 27°29′N, 97°48′E, elevation 540 m, 118 km south of the Tibetan border and 53 km west of the border with Yunnan Province, China. The purpose of the trip was to inventory the poorly known avifauna of the premontane temperate rainforest habitat at that site. On 6 February 2004, we captured two scimitar-babblers that appeared to be representatives of the genus Jabouilleia. An additional individual of the taxon was captured in the same vicinity on 8 February 2004. These were the first records for Jabouilleia from Myanmar, and subsequent investigation showed that these specimens were members of a previously undescribed species, which we...

Characterization of Estrous Cyclicity in the Sable Antelope(Hippotragus niger)through Fecal Progestagen Monitoring

Fecal progesterone metabolite monitoring techniques were validated for the sable antelope and used to characterize ovarian cycle dynamics and reproductive seasonality in a captive population at the National Zoological Park's Conservation and Research Center. Hormone was homogeneously distributed within fecal samples. Longitudinal fluctuations in fecal progesterone metabolites were consistent with typical luteal phase patterns and corresponded closely with changes in serum progesterone. The lag time from an im injection of progesterone to peak excretion in feces was 16 h. The pattern of births showed a slight peak in the summer (May–July), but year-round endocrine monitoring of six nonpregnant females showed no evidence of seasonality in ovarian activity. Females exhibited 11–14 estrous cycles per year, averaging 24.2 ± 0.9 days in length. Luteal and interluteal phases were 18.4 ± 0.9 and 5.8 ± 0.4 days in length, respectively. Although only a small number of hippotragine antelope species have been studied, data indicate that they exhibit considerable interspecific variability in estrous cycle length and reproductive seasonality and thus may be a useful group for further investigation of factors regulating fertility.

Play-partner preferences and the function of social play in infant sable antelope, Hippotragus niger

Play-partner preferences were investigated in 38 sable antelope calves observed in semi-captivity at the National Zoological Park's Conservation and Research Center near Front Royal, Virginia. All calves initiated play with peers but rarely played with yearlings or adults. Calves initiated play with most calves in their cohort but had strong preferences for one or two peers. Preferences were highly symmetrical and stable over time. Partners of similar age were preferred. Calves did not prefer individuals of the same sex, nor did they consistently favour individuals of one sex over the other. Calves initiated less play with related peers than expected by chance. Patterns of play-partner preference in infant sable antelope supported the concept of play as self assessment, whereby individuals continually compare their developmental competence with that of their peers.

The attractiveness of a liquid bait to white-tailed deer in the Central Appalachian Mountains, Virginia, USA.

We determined the attractiveness of a bait composed of apple juice, apple odor, water, glycerin, and salt to captive white-tailed deer (Odocoileus virginianus) at the National Zoological Park Conservation and Research Center, Front Royal, Virginia, USA. Thirty-nine deer (three adult males, 20 adult females, eight male fawns, eight female fawns) were presented with the bait formulation in a 22-ha enclosure during January, February, and May 1994. Daily consumption, and the frequency of visits to bait dispensers and the frequency of drinking bouts were recorded. Overall consumption was greatest in May (P < 0.001). While adults and fawns visited bait dispensers equally often, fawns drank more frequently (P < 0.001).

Maternal strategies in sable antelope,Hippotragus niger: Factors affecting variability in maternal retrieval of hiding calves

Maternal behavior of wild ungulates has long been considered relatively invariant, yet recent reports from both wild and captive populations indicate considerable variability. Maternal behavioral tactics associated with the “hider” developmental strategy were investigated in six mother-infant pairs of sable antelope, Hippotragus niger, at the National Zoological Park's Conservation and Research Center near Front Royal, Virginia. When a calf moved away from its mother to hide, the mother tended to be 10 or more body lengths away and facing away from the calf. The presence of maternal vocalizations and the mother's ability to orient to the calf's resting site prior to calf activity periods were dependent on the age of the calf and whether the calf was lying alone or with other calves. The presence of maternal vocalizations and the ability of a mother to orient toward her calf were negatively related, with the mother vocalizing only when her calf could not be located visually. Variability in maternal behavior when searching for hidden calves was best explained by differences in calf conspicuousness. A mother apparently remembered only the general area in which her calf was lying, and not the precise location. Comparison of this study with previous studies of captive sable antelope suggests that mother-infant interactions are strongly influenced by enclosure size and the availability of tall vegetation; therefore, behaviors of individuals observed in small captive enclosures lacking tall vegetation may not be representative of those in the wild. © 1996 Wiley-Liss, Inc.

Flehmen and birth synchrony among female sable antelope,Hippotragus niger

The role of female flehmen behaviour in maintaining reproductive synchrony was investigated in 11 adult female sable antelope and their associated offspring maintained on a 13·2-ha pasture at the National Zoological Park's Conservation and Research Center near Front Royal, Virginia. All occurrences of aggression and flehmen by adult females were recorded during 274h of observation over a 10-month period (1987), and the timing of births was recorded for four birth seasons (1986-1989). In each year, dominant females tended to give birth in temporal proximity to other females (birth clustering), while subordinates gave birth asynchronously. Flehmen frequency fluctuated seasonally, reaching highest levels just prior to the approximated time of conception. Adult, multiparous females were the primary targets of flehmen. There was positive assortment by reproductive state: pregnant females attended to urinations by other pregnant females and postpartum females responded to other postpartum females. Prepartum flehmen rates reliably predicted subsequent birth synchrony, and the degree of synchrony between a given pair of females was directly proportional to the frequency with which they sampled each other's urine in the preceding year. These results indicate that flehmen is a potential mechanism by which female sable antelope can manipulate the timing of both conception and parturition.

Long-Term Trends in Habitat Selection by Kentucky Warblers

-Microhabitat selection of the Kentucky Warbler (Oporornis formosus), a forestinterior Neotropical migrant, was examined using a geographical information system. The distribution of territorial male Kentucky Warblers was mapped within a 460-ha study area in northwestern Virginia from 1979 through 1992. Each annual distribution of territories was compared, using logistic regression, to a random distribution of territories with respect to habitat features codified within a vector-based geographical information system. Kentucky Warblers selected forested areas with cove hardwoods and avoided oak/hickory overstory. The warblers also were found more often in areas that contained streams and in areas with low white-tailed deer (Odocoileus virginianus) densities. Since 1979 there have been significant shifts in Kentucky Warbler use of habitat at this site, resulting in fewer territories within oak/hickory and edge habitats. Received 22 November 1993, accepted 31 August 1994. KENTUCKY WARBLERS (Oporornis formosus) are insectivorous, ground-nesting birds that breed within the interior forests of the northeastern United States and winter from southern Mexico to South America. This species is one of many wood-warblers that has shown an apparent decline over the last two decades (Robbins et al. 1989) and, therefore, is of particular interest to land managers and conservationists. In studies using multivariate analysis to describe forest bird communities, Kentucky Warblers were found to be associated with large, mature forests that possess a dense understory (Lynch and Whigham 1984, Robbins et al. 1989). As with most wood-warbler species, however, little is known of specific microhabitat requirements beyond the valuable, but anecdotal, reports from early naturalists (Chapman 1907, DeGaris 1936, Bent 1953) and annual surveys that detected population declines (Robbins et al. 1989). Declines within some unmanaged forests have been postulated to be due to an increased density of white-tailed deer (Odocoileus virginianus; Boone and Dowell 1986, Robbins 1991) through reduced density of understory shrubs. Geographical information systems (GIS) have been used successfully to model habitat requirements of Sage Grouse (Centrocercus urophasianus; Homer et al. 1993) and Wild Turkey (Meleagris gallopavo; Donovan et al. 1987). These models, however, identified landscape-scale features that were associated with flocks or populations of birds and, thus, may be inappropriate for analysis of habitat use by individual birds within a forest block. Given that Kentucky Warblers inhabit mature, deciduous forests, it may be possible to determine how they are distributed within this landscape-scale habitat using a GIS. Since 1979 extensive surveys for Kentucky Warblers have been conducted at the National Zoological Park's Conservation and Research Center (CRC). This site is a small (1,200-ha), protected area in the Blue Ridge Mountains of Virginia, 5 km south-southeast of Front Royal, Virginia. These annual surveys can be compared to vegetation and habitat attribute maps recently produced for the study area with a GIS. We examine: whether landscape level features and habitat measures derived from aerial photographs, when organized within a GIS, are suitable for quantifying habitat requirements of small forest birds; whether shifts in habitat use are detectable; and what factors might precipitate habitat shifts.

Ontogeny of Flehmen in Sable Antelope, Hippotragus niger

AbstractFlehmen, a conspicuous posture characterized by eversion of the upper lip, facilitates the transfer of nonvolatile urinary chemicals to the vomeronasal organ and therefore has been implicated in the control of reproduction in ungulates. The ontogeny of urine sampling and flehmen was investigated in semi‐free‐ranging sable antelope, Hippotragus niger, at the National Zoological Park's Conservation and Research Center because behavioural evidence suggests that flehmen is a mechanism of reproductive synchronization among females. During the first year of life, flehmen rates increased with age in both sexes. Flehmen rates of female calves equalled those of adult females by 4 months of age. Male calves first exhibited flehmen at younger ages than did female calves and showed greater increases in flehmen rate during development. Both sexes exhibited flehmen primarily after sampling urine of female conspecifics as it was being voided. During the first 2 months of life, sable antelope preferred to sample urine of other calves, but by 1 year of age adult females were the preferred targets. Females approaching sexual maturity preferred to sample urine from postpartum females (presumably resuming oestrous cycling) rather than from pregnant females, as expected if they were attempting to synchronize oestrus with experienced females. Results are consistent with the hypothesis that flehmen serves to coordinate reproduction among females and further suggest that flehmen may affect reproductive maturation.

Early Mother-Young Relations in White-Tailed Deer

During 1986–1988, mother-young relations in white-tailed deer ( Odocoileus virginianus ) were studied at the National Zoological Park's Conservation and Research Center. During the first few weeks after parturition, mothers associated very little with their fawns and periods of contact were brief; they visited their fawns predominantly at sunrise and sunset. Later, fawns were visited randomly, and time of contacts and length of time between successive contacts became variable. Mothers kept the shortest distances during the first 2 weeks; distances then increased and remained constant. Up to 4 weeks of age, distances were shortest at night, but later, mothers were located farthest from their fawns during this time. Mother-young distances during times of reunion also increased with age. Behavioral differences between sexes began to unfold in mother-young relationships as early as 3 weeks after birth and persisted throughout the first 3 months. Males associated less and more loosely with their mothers than females.

Social and spatial organization of female white-tailed deer, Odocoileus virginianus, during the fawning season

Abstract. From 1986 until 1988 social and spatial relationships of 11 parturient female white-tailed deer were monitored at the National Zoological Park's Conservation and Research Center to determine their degree and duration of isolation from conspecifics. Social isolation at and following parturition was indicated by decreased association with other parturient females and with their own previous offspring. Parturient females also showed characteristic patterns of spacing behaviour that resulted in complete segregation of core home ranges. These areas encompassed nearly all bedding sites of fawns during the first 6 weeks following parturition and conspecifics were repulsed through overt aggression. The exclusive use, the annual fidelity to these postpartum home ranges and the active repulsion of intruders indicated that female white-tailed deer are territorial during the first weeks postpartum. Predation pressure and the risk of misdirected imprinting may have had a combined effect on the evolution of this territoriality.

Aggressive behavior and dominance hierarchies in female sable antelope, Hippotragus niger: Implications for captive management

AbstractSocial interactions of adult female sable antelope, Hippotragus niger, were observed at the National Zoological Park's Conservation and Research Center. Aggressive behavior was quantified for two herds containing 8 and 11 females. Aggression was lowest at calving, and highest near the time of conception. Dominance hierarchies were strictly linear and stable over time. Dominance rank was highly correlated with age, with the oldest females achieving highest rank. High‐ranking females initiated more aggression and were more likely to behave aggressively towards a newly introduced adult female. The newly introduced individual was the victim of prolonged, intense group chases and was permanently excluded from the herd. Low‐ranking females directed more aggression at yearling herd members than did high‐ranking females. Temporary absences by herd members resulted in long‐lasting, substantial increases in received aggression upon their return. Because of their aggressive nature, sable antelope present a challenge to captive management. © 1993 Wiley‐Liss, Inc.

Flehmen and social dominance in captive female sable antelope, Hippotragus niger

The relationship between female dominance and flehmen was investigated in a herd of 11 female sable antelope ( Hippotragus niger) maintained in a 13.2-ha pasture at the National Zoological Park's Conservation and Research Center in Front Royal, VA, U.S.A. All occurrences of aggression and flehmen by adult females were recorded during 274 h of observation over a 9 month period. Overall frequencies of flehmen were highly correlated with rank, dominant females exhibiting the highest flehmen rates. Subordinates rarely performed flehmen in response to urination by higher ranking females. When aggression immediately preceded opportunities for flehmen, dominants virtually always performed flehmen while subordinates never did. Investigation of urine on the substrate was unrelated to rank, suggesting that subordinates may exploit alternate strategies for social investigation. Flehmen may allow synchronization of reproduction by enabling females to assess each other's reproductive condition. High ranking females showed the greatest degree of reproductive synchrony within the herd.

Terrestrial Gastropod Hosts of Parelaphostrongylus tenuis at the National Zoological Park's Conservation and Research Center, Virginia

Terrestrial gastropods at the National Zoological Park's Conservation and Research Center (CRC) near Front Royal, Virginia, were surveyed from June 1985 to May 1986, to assess their role in transmission of the meningeal worm, Parelaphostrongylus tenuis. A total of 670 gastropods representing 9 families and 18 species was collected. The slug Deroceras laeve accounted for 50.4% of the specimens collected. Parelaphostrongylus tenuis infections were found in 15 gastropods (2.2% prevalence) representing 5 species; 5 of the infected gastropods were D. laeve. New host records for this nematode are Ventridens collisella and Philomycus carolinianus. Infected gastropods were recovered from June through October 1985 and in May 1986. All 6 sampling locations yielded infected gastropods, suggesting this parasite is widely distributed at the CRC, and is therefore likely to continue to pose a serious threat to exotic ungulates maintained there for conservation and research purposes.

Management of White‐tailed deer Odocoileus virginianus at the National Zoological Park's Conservation and Research Center

Management of White‐tailed deer Odocoileus virginianus at the National Zoological Park's Conservation and Research Center

Management of White-tailed deer Odocoileus virginianus at the National Zoological Park's Conservation and Research Center

Management of White-tailed deer Odocoileus virginianus at the National Zoological Park's Conservation and Research Center