Vocal Repertoire and Intraspecific Variation within Two Loud Calls of the Small-Eared Greater Galago (Otolemur garnettii) in Tanzania and Kenya

Bettridge, Caroline M.; Kenworthy, Simon P.; Butynski, Thomas M.; Jong, Yvonne A. de; Kort, Selvino R. de

doi:10.1159/000500260

Cited by 7 publications

(10 citation statements)

References 56 publications

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“…Inter-unit intervals of tree hyrax calls were calculated from sequences when the animal was calling alone. Otolemur trailing calls and Paragalago incremental calls were compared with calls described in previous studies [12,13,52].…”

Section: Discussionmentioning

confidence: 99%

“…Otolemur garnettii has an extensive vocal repertoire with 12 different call types [13,50]. Otolemurs in Taita Hills also have several different calls, but the only loud calls they use are the trailing call and the cluster squawk.…”

Section: Discussionmentioning

confidence: 99%

“…The Taita Hills are situated near the transition zone between the ranges of two small-eared greater galago subspecies, Otolemur garnettii lasiotis and O. g. panganiensis [96]. We thus compared the trailing calls of O. g. panganiensis [13], O. g. lasiotis [11], and the Otolemurs from the Taita Hills (Table 5). Acoustic comparison confirms that the subspecies in the Taita Hills is O. g. lasiotis.…”

Section: Discussionmentioning

confidence: 99%

“…The only Otolemur species recorded from the Taita Hills is O. garnettii [60]. O. garnettii is divided into several subspecies; the one that occurs in the Taita Hills is presumed to be O. g. lasiotis, but the known distribution limits of another subspecies, O. g. panganiensis, are not located far off [13]. The subspecific identity of the Taita Hills greater galago thus requires confirmation.…”

Section: Galago Taxonomymentioning

confidence: 99%

“…Loud calls that are used in long-range advertising are qualitatively different between species [8]. For example, many recently described galago species have been originally identified by their advertisement calls [9][10][11][12][13]. In Paragalago cocos and P. zanzibaricus taxonomic separation based on acoustic properties of an advertisement call was subsequently confirmed by genetic analysis [14].…”

Section: Introductionmentioning

confidence: 99%

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

et al. 2020

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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.

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Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Galago Taxonomymentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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

et al. 2020

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Factors affecting call usage in wild black-and-white ruffed lemurs (Varecia variegata) at Mangevo, Ranomafana National Park

et al. 2021

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Distribution, Population Density, and Behavior of Dwarf Galagos (Paragalago sp.) in Taita Hills, Kenya

Rosti,

Heiskanen,

Bearder

et al. 2023

Int J Primatol

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A good understanding of taxonomy, distribution, and population density is needed for conservation. Scientific knowledge of dwarf galagos (Paragalago sp.) remains limited. Two populations of Taita dwarf galagos survive in the largest remnants of moist montane forest in Taita Hills, Kenya. We obtained acoustic data on the two remaining populations using AudioMoths—small, passive recorders—more than 231 h in January and February 2021. We measured forest structure by using airborne LiDAR and ground-level observations and tested the influence of forest size and height, canopy coverage, and density on calls per hour as an indicator of population density. Forest size significantly affected population size. Taita dwarf galagos prefer dense canopy coverage, and they prefer the lower 20–30-m tall forest. Mbololo forest (185 ha) has steady population, whereas dwarf galagos are nearly extinct in Ngangao forest (120 ha). The calls of Taita dwarf galagos resemble those of Kenya coast dwarf galagos (Paragalago cocos). DNA studies are urgently needed to resolve the taxonomic status of both surviving populations of dwarf galagos in the Taita Hills. This simple study design should be conducted across African forests to obtain crucial knowledge for galago conservation.

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Vocal Repertoire and Intraspecific Variation within Two Loud Calls of the Small-Eared Greater Galago (Otolemur garnettii) in Tanzania and Kenya

Abstract: Vocal repertoire and intraspecific variation within long-distance calls of the small-eared greater galago (Otolemur garnettii) in Tanzania and Kenya

Cited by 7 publications

References 56 publications

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

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

Factors affecting call usage in wild black-and-white ruffed lemurs (Varecia variegata) at Mangevo, Ranomafana National Park

Distribution, Population Density, and Behavior of Dwarf Galagos (Paragalago sp.) in Taita Hills, Kenya

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