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Two independent methods were used to quantify abundances and population structure of two paruline wood warblers, the American Redstart (Setophaga ruticilla) and Black-throated Blue Warbler (Dendroica caerulescens), wintering in Jamaica,... more
Two independent methods were used to quantify abundances and population structure of two paruline wood warblers, the American Redstart (Setophaga ruticilla) and Black-throated Blue Warbler (Dendroica caerulescens), wintering in Jamaica, West Indies. One conventional 10-min point count was followed by 5 min each of redstart, then Blackthroated Blue Warbler vocalizations (a mixture of territorial songs and chip notes recorded during the breeding season) at each of 585 points in 18 habitats. Age and sex composition of the target species were recorded along with observations of other species. Compared with conventional point counts, those supplemented with playback of vocalizations (1) detected 3.0 and 2.3 times more American Redstarts and Black-throated Blue Warblers, respectively, (2) disclosed significantly more individuals of three other migrant warbler species and one year-round resident species belonging to the "warbler guild," (3) facilitated identification of age and sex of target species by attracting them closer to the observer, and (4) confirmed that wintering individuals of both species of warbler were dispersed as expected for a territorial species. Compared with yearling males and with females, older redstart males were observed significantly more frequently during playbacks than predicted by pre-playback relative frequencies. No such sex bias was found for Black-throated Blue Warblers, a species in which age cannot be reliably determined except with hand-held individuals. Diurnal variation in surveyed abundances of both species was relatively minor, but was significantly less pronounced for playback counts than for pre-vocalization counts in Black-throated Blue Warblers. Our results indicate that broadcast territorial advertisement vocalizations provide a powerful tool to study the ecology and distribution of neotropical migrant songbirds in winter.
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Abstract: Tapirs are a taxonomic group with a high susceptibility to mycobacterial diseases. However, successful therapy has only been documented sporadically. Here treatment of mycobacteriosis diagnosed in three, one male and two female,... more
Abstract: Tapirs are a taxonomic group with a high susceptibility to mycobacterial diseases. However, successful therapy has only been documented sporadically. Here treatment of mycobacteriosis diagnosed in three, one male and two female, lowland tapirs (Tapirus terrestris) in a zoo in Germany is reported. Two of the animals showed chronic mild respiratory signs, and conventional therapy did not improve the condition. Culture of broncho-alveolar lavage (BAL) samples was positive for Mycobacterium avium ssp. hominissuis. Upon airway endoscopy, bronchial edema and increased mucus production were visible. Initially, all three infected tapirs received oral antimycobacterial therapy consisting of 5 mg/kg body weight isoniazid, 10 mg/kg rifampicin, and 10 mg/kg clarithromycin q24h. Based on therapeutic drug level monitoring, the doses of rifampicin were adjusted to 12 and 15 mg/kg in the females and the male, respectively. The treatment with all three drugs was continued for 11 mon. Six months into treatment, the clinical condition resolved, and repeated BAL samples of all three tapirs tested negative for mycobacteria by culture. Here the approach for a treatment protocol with minimal side effects suitable to control infections with nontuberculous mycobacteria in lowland tapirs is reported.
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The scentmarking glands of the anal pouch, penile pad, and the forefoot of the aardwolf (Proteles cristatus) were studied by histological, histochemical, immunohistochemical methods, and by electron microscopy. The morphological... more
The scentmarking glands of the anal pouch, penile pad, and the forefoot of the aardwolf (Proteles cristatus) were studied by histological, histochemical, immunohistochemical methods, and by electron microscopy. The morphological observations are correlated with eco-ethological aspects of this nocturnal animal. In all studied regions there was a superficial layer of holocrine sebaceous glands and a deeper layer of apocrine scent glands; these two types of glands apparently function in concert. Only in the forefoot were additional tubular glands, resembling eccrine sweat glands found, which may improve the frictional capacities of the paw, while apocrine and holocrine glands serve scent-marking functions of the forefoot. Penile pad and anal pouch are exclusively scent marking organs. The secretion modus of the apocrine glands is both via exocytosis and apocrine mechanism. Homogeneous apical, secretory granules, which contain glycoproteinaceous material, represent evidence for exocytosis. In the anal pouch, additional variably sized granules contain endogenous pigments which are probably responsible for the brownish coloration of the secretory product of the male animals. Variable heights of the glandular cells, frequent apical tall protrusions as well as pinched-off pieces of cytoplasm in the glandular tubules support the concept of an apocrine secretion in the scent glands. The immunohistochemical staining pattern of actin points to the involvement of actin filaments in the pinching-off process of the apical cell protrusion, which does not contain any cell organelles. The variable actin staining patterns suggest a dynamic process during which actin filaments form a ring or sheet at the basis of the pinching-off bleb. Proliferative and apoptotic phenomena show no preference for active and inactive glandular cells suggesting that replacement of cells occurs independently of the functional status of the glands.
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ABSTRACT A radio-collared, female black-footed cat (Felis nigripes) was followed for a total period of 575 hours, over seven observation periods spanning 18 months, in the Kimberley region of the Northern Cape Province, South Africa. Data... more
ABSTRACT A radio-collared, female black-footed cat (Felis nigripes) was followed for a total period of 575 hours, over seven observation periods spanning 18 months, in the Kimberley region of the Northern Cape Province, South Africa. Data on reproduction and scent marking were collected by direct observation. The predominant form of scent marking was urine-spraying, the frequency of which fluctuated during the year and seemed to be related to changes in the reproductive cycle. Marking frequency increased dramatically approximately one and a half months before mating, and conception of the first litter of the breeding season occurred at a low frequency during pregnancy, and was entirely absent when the cat was rearing young. This strongly indicates a primary function in the advertisement of female reproductive condition, although an additional role in the maintenance of social spacing is suggested. Scent marks were not restricted to the borders of the animal's range, but corresponded to those areas used most intensely during the year.
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There are only about 7,100 adolescent and adult cheetahs remaining in the wild. With the majority occurring outside protected areas, their numbers are rapidly declining. Evidence-based conservation measures are essential for the survival... more
There are only about 7,100 adolescent and adult cheetahs remaining in the wild. With the majority occurring outside protected areas, their numbers are rapidly declining. Evidence-based conservation measures are essential for the survival of this species. Genetic data is routinely used to inform conservation strategies, e.g., by establishing conservation units (CU). A commonly used marker in conservation genetics is mitochondrial DNA (mtDNA). Here, we investigated the cheetah's phylogeography using a large-scale mtDNA data set to refine subspecies distributions and better assign individuals to CUs. Our dataset mostly consisted of historic samples to cover the cheetah’s whole range as the species has been extinct in most of its former distribution. While our genetic data largely agree with geography-based subspecies assignments, several geographic regions show conflicting mtDNA signals. Our analyses support previous findings that evolutionary forces such as incomplete lineage sorting or mitochondrial capture likely confound the mitochondrial phylogeography of this species, especially in East and, to some extent, in Northeast Africa. We caution that subspecies assignments solely based on mtDNA should be treated carefully and argue for an additional standardized nuclear single nucleotide polymorphism (SNP) marker set for subspecies identification and monitoring. However, the detection of the A. j. soemmeringii specific haplogroup by a newly designed Amplification-Refractory Mutation System (ARMS) can already provide support for conservation measures.
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ABSTRACT A radio-collared, female black-footed cat (Felis nigripes) was followed for a total period of 575 hours, over seven observation periods spanning 18 months, in the Kimberley region of the Northern Cape Province, South Africa. Data... more
ABSTRACT A radio-collared, female black-footed cat (Felis nigripes) was followed for a total period of 575 hours, over seven observation periods spanning 18 months, in the Kimberley region of the Northern Cape Province, South Africa. Data on reproduction and scent marking were collected by direct observation. The predominant form of scent marking was urine-spraying, the frequency of which fluctuated during the year and seemed to be related to changes in the reproductive cycle. Marking frequency increased dramatically approximately one and a half months before mating, and conception of the first litter of the breeding season occurred at a low frequency during pregnancy, and was entirely absent when the cat was rearing young. This strongly indicates a primary function in the advertisement of female reproductive condition, although an additional role in the maintenance of social spacing is suggested. Scent marks were not restricted to the borders of the animal's range, but corresponded to those areas used most intensely during the year.
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For conservation breeding, the endangered Lion-tailed Macaques have been maintained in North America under SSP since 1983 and in Europe under EEP since 1989. Based on a growing interest to support the species long-term survival, the SSP... more
For conservation breeding, the endangered Lion-tailed Macaques have been maintained in North America under SSP since 1983 and in Europe under EEP since 1989. Based on a growing interest to support the species long-term survival, the SSP population increased considerably during the first few years of the programme but due to space problems and resulting birth control measures, it has drastically declined to small numbers and a non- breeding status at present. The EEP population continually increased till 2012, but due to the lack of spaces and birth control practises, it has gradually declined since then. It is emphasised that the knowledge gained from field studies on Lion-tailed Macaques in India and its incorporation for captive management under EEP has helped develop appropriate management strategies. Captive propagation of the Lion-tailed Macaque in India, the habitat country, can profit from the successes and drawbacks of the long-term management experiences of SSP and EEP.
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There are only about 7,100 adolescent and adult cheetahs remaining in the wild. With the majority occurring outside protected areas, their numbers are rapidly declining. Evidence-based conservation measures are essential for the survival... more
There are only about 7,100 adolescent and adult cheetahs remaining in the wild. With the majority occurring outside protected areas, their numbers are rapidly declining. Evidence-based conservation measures are essential for the survival of this species. Genetic data is routinely used to inform conservation strategies, e.g., by establishing conservation units (CU). A commonly used marker in conservation genetics is mitochondrial DNA (mtDNA). Here, we investigated the cheetah's phylogeography using a large-scale mtDNA data set to refine subspecies distributions and better assign individuals to CUs. Our dataset mostly consisted of historic samples to cover the cheetah’s whole range as the species has been extinct in most of its former distribution. While our genetic data largely agree with geography-based subspecies assignments, several geographic regions show conflicting mtDNA signals. Our analyses support previous findings that evolutionary forces such as incomplete lineage sort...
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Abstract: The efficacy, safety, physiologic effects, and reversibility of butorphanol-medetomidine-midazolam (BMM) immobilization were evaluated in black-footed cats (Felis nigripes) and compared between captive and wild animals. Nine... more
Abstract: The efficacy, safety, physiologic effects, and reversibility of butorphanol-medetomidine-midazolam (BMM) immobilization were evaluated in black-footed cats (Felis nigripes) and compared between captive and wild animals. Nine captive and 14 wild black-footed cats were hand injected into an accessible hind limb muscle group with the BMM combination. The captive cats (captive group) received a lower dose of the combination (butorphanol, 0.25 ± 0.03 mg/kg; medetomidine, 0.06 ± 0.01 mg/kg; midazolam, 0.13 ± 0.02 mg/kg), whereas the wild cats received a higher dose (butorphanol, 0.53 ± 0.11 mg/kg, medetomidine, 0.13 ± 0.03 mg/kg, midazolam, 0.27 ± 0.05 mg/kg). Two capture methods were required to restrain the wild cats; previously collared cats were tracked and excavated out of their burrows during daylight hours (excavated group), whereas uncollared cats were randomly located using spotlights and pursued by a vehicle at night (pursued group). Inductions were rapid and no spontaneous arousals occurred. Mean arterial blood pressure in all cats was within normal limits for domestic cats. Initial rectal temperatures varied greatly among the groups, but decreased in all groups as the immobilization progressed. In the pursued animals, heart rates and respiratory rates were initially elevated. All cats had moderate hypoxemia, hypocapnia, and metabolic acidosis. Intramuscular administration of naltrexone, atipamezole, and flumazenil resulted in rapid, uncomplicated recoveries. BMM is thus a safe, effective immobilizing drug combination for both captive and wild black-footed cats, but higher doses are required in wild animals. The capture methods exerted a greater influence on the physiology of the immobilized animals than did the doses of the drugs used. Although this drug combination can be used safely to immobilize black-footed cats, supplemental oxygen should always be available for use, especially in pursued animals due to hypoxia.
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The saiga (Saiga tatarica, Bovidae, Cetartiodactyla) is facing a precarious situation in the wild and unfortunately also zoos have failed so far in establishing a stable captive population. Cologne Zoo was one of the most successful zoos... more
The saiga (Saiga tatarica, Bovidae, Cetartiodactyla) is facing a precarious situation in the wild and unfortunately also zoos have failed so far in establishing a stable captive population. Cologne Zoo was one of the most successful zoos in holding and breeding this endangered species. We analysed life history and breeding of the Cologne animals. We highlight differences between wild and captive saigas and potential trouble spots for captive breeding. Being seasonal breeders, oestrus length usually lasted 1–2 days with an average time of 19.85 days between oestrus periods if not pregnant. Gestation lengths lasted 133–151 days with gestations of twins 4.39 days shorter on average than for one lamb. Bearing twins was not a rule for the Cologne saigas. We found correlations between litter size and the age of the female or the number of births of the female, respectively. A disparity between the theoretically possible number of offspring and the actual number born emphasises the need to...
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Study Area: Benfontein Game Farm, owned by De Beers Consolidated Mines, lies 10 km SE of Kimberley on the border of the Northern Cape and Free State Provinces in central South Africa. The majority of the 11.400 ha of arid plant... more
Study Area: Benfontein Game Farm, owned by De Beers Consolidated Mines, lies 10 km SE of Kimberley on the border of the Northern Cape and Free State Provinces in central South Africa. The majority of the 11.400 ha of arid plant communities have been the subject of the first in-depth field study on the black-footed cat (Sliwa 1993, 1994, 2004; 2006, Olbricht & Sliwa 1997), which largely defines the present day knowledge on densities, habitat preference, ecology and behaviour of the species.
This study attempted to answer how scent marks functio n in terms of aardwolf Proteles cristatus yearround territory maintenance and mating success. A fun ctional analysis of scent marking in the aardwolf was conducted in a two and a half... more
This study attempted to answer how scent marks functio n in terms of aardwolf Proteles cristatus yearround territory maintenance and mating success. A fun ctional analysis of scent marking in the aardwolf was conducted in a two and a half year field study wh ilst recording 42 000 paste marks. The anatomy and histology of the anal pouch revealed an efficient organ for producing copious amounts of longlasting fatty pasting secretion, and the apparatus for applying it onto grass stalks. The histology of the penile pad of aardwolf males was similarly geared to production and application of secretion, though its exact function is still not clear. Aardwolves starte d practising scent marking motor patterns early in life, but physiological maturation of secretion was com plete with eight months and independence from their parents only. Cubs practised paste marking by over marking scent marks of their parents, adjusting their mark-rate to that of the adult followed. Afte r physical and beha...
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A fifth of all known species are currently classified as threatened in the wild: the rate of biodiversity loss is rapid, continuous, and mostly due to anthropogenic activities. To slow down this decline, the accurate estimation of... more
A fifth of all known species are currently classified as threatened in the wild: the rate of biodiversity loss is rapid, continuous, and mostly due to anthropogenic activities. To slow down this decline, the accurate estimation of demographic parameters for threatened species is critical. With this aim, zoo institutions play an important role, giving access to data on zoo-housed animals, which aids researchers working on species life-history traits and intrinsic factors influencing the fitness of both sexes, such as age. While tigers (Panthera tigris) are particularly threatened in their natural environment, few of their demographic parameters have been determined because of their solitary and elusive nature as well as low population density. Using individual-based information for more than 9200 tigers (from 1938 to 2018) recorded in the International Tiger Studbook 2018, we aimed to determine sub-species and sex-specific variability of survival and reproductive parameters with age....
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Several studies have shown higher costs of rearing sons than daughters in mammals where males are larger than females. These studies typically focus on females by examining how the offspring sex ratio during a single reproductive event... more
Several studies have shown higher costs of rearing sons than daughters in mammals where males are larger than females. These studies typically focus on females by examining how the offspring sex ratio during a single reproductive event affected mothers’ subsequent reproduction or survival probability. Here, we examine relationships between offspring sex ratio during single or multiple reproductive events and several survival metrics in mothers and fathers, using data from zoo‐housed tigers (Panthera tigris) and ruffed lemurs (Varecia sp.). Our analyses failed to reveal an overall cost of reproduction or a higher cost of sons to mothers. In male ruffed lemurs, the proportion of sons produced during early life (before 10 years old) was negatively correlated with lifespan later in life. In tigers, males with a higher proportion of sons during their lifetime had shorter lifespans. One likely mechanism is the difference in testosterone levels between males: a high concentration of testos...