Vocalization Analyses of Nocturnal Arboreal Mammals of the Taita Hills, Kenya

Three poorly known nocturnal mammal species from the montane forests of the Taita Hills in Kenya, were studied via vocalization analysis. Here, their acoustic behaviour is described. The studied animals were the tree hyrax (Dendrohyrax sp.), the small-eared greater galago (Otolemur garnettii), and the dwarf galago (Paragalago sp.). High-quality loud calls were analysed using RAVEN PRO, and compared to calls of presumed closest relatives. Our findings include the first detailed descriptions of tree hyrax songs. Moreover, our results suggest that the tree hyrax of Taita Hills may be a taxon new to science, as it produces a characteristic call, the ‘strangled thwack’, not previously known from other Dendrohyrax populations. Our data confirms that the small-eared greater galago subspecies living in the Taita Hills is Otolemur garnettii lasiotis. The loud calls of the elusive Taita Hills dwarf galago closely resemble those of the Kenya coast dwarf galago (Paragalago cocos). Thus, the population in the Taita Hills probably belongs to this species. The Taita Hills dwarf galagos are geographically isolated from other dwarf galago populations, and live in montane cloud forest, which is an unusual habitat for P. cocos. Intriguingly, two dwarf galago subpopulations living in separate forest patches in the Taita Hills, Ngangao and Mbololo, have clearly different contact calls. The Paragalagos in Mbololo Forest may represent a population of P. cocos with a derived call repertoire, or, alternatively, they may actually be mountain dwarf galagos (P. orinus). Hence, differences in habitat, behaviour, and contact call structure suggest that there may be two different Paragalago species in the montane forests of the Taita Hills.

A Comparison of the Efficacy and Cardiopulmonary Effects of 3 Different Sedation Protocols in Otolemur garnettii

The Northern greater galago (Otolemur garnettii) is a prosimian primate most commonly used to study the evolutionary development of vision and somatosensation. This study aimed to investigate the efficacy and cardiopulmonary effects of 3 sedation protocols commonly used in other primate species: 1) alfaxalone (Alf; 8 mg/kg IM) 2) ketamine alone (Ket; 20 mg/kg IM) and 3) ketamine + dexmedetomidine (Ket+Dex; 4 mg/kg + 25 μg/kg IM) with reversal (atipamezole; 250 μg/kg IM). A total of 34 animals were evaluated, including 11 juveniles and 23 adults. Cardiopulmonary parameters such as indirect blood pressure, heart rate, respiratory rate, and SpO2 were measured, and blood was collected for blood gas analysis and a chemistry panel. To examine the efficacy of each sedation protocol, induction time, immobilization time, and recovery time were recorded. Subjective measures of quality and efficacy included quality of induction, pedal withdrawal reflex, palpebral reflex, muscle tension, rectal temperature, and quality of recovery. All 3 protocols successfully immobilized the animals and all animals recovered from sedation. Heart rates were highest among the Ket group and the lowest for the Ket+Dex group. On average, the Alf group was immobilized for twice as long as either the Ket or Ket+Dex groups. The Ket+Dex group had the fastest average recovery time and subjectively had the best quality of recovery. Based on these results, Ket+Dex is recommended over Alf or Ket alone for brief sedation of healthy galagos.