Animals of Taita, Kenya

Tag: dassie

  • Peculiar features of hyraxes

    Peculiar features of hyraxes

    Three genuses are recognized:

    1. Dendrohyrax – tree hyraxes – 4 species at the moment – more to come
    2. Heterohyrax – bush hyrax – 1 species + 20+ subspecies
    3. Procavia – rock hyrax – 1 species +17 subspecies – and some of them are species
    Taita tree hyrax (Dendrohyrax sp.)

    Some features

    • small mammals 1.8-5.5 kg
    • no visible tail
    • coat dense and light grey to dark brown
    • all three genera are highly vocal
    Bush hyrax from Plzen Zoo, Czech. They are smaller, grayish, and they have very strong white patches above the eyes. They are not as round as rock hyrax and tree hyraxes.

    Unusual features

    • dorsal gland with hair with different color
    • tactile hairs around the body (length up to 8 cm)
    • forefoot has four digits and hindfoot three
    • stomach divided into two chambers
    • highly subdivided liver – plant food they use may be toxic
    • internal testes
    • unbranched caecum acts as a fermentation chamber that produces large amounts of volatile fatty acids that serve as an energy source
    • effective kidney function, they have high capacity for concentrating urea, and excreting large amounts of undissolved calcium carbonate.
    • many species defaecate to specific spots, and many species use latrines
    • low metabolic rate
    • they have poor ability to regulate their body temperature
    • body temperature is is maintained by behavioral thermoregulation
    • gestation period is long 6-8 months

    Odd appearance has caused confusion

    • First they were thought to be rodents, thus genus Procavia (cavia meaning before guinea pigs)
    • Later called hyrax – equally wrong – as “shrew mouse”
    • Dassie used in South Africa comes from Dutch badger – das
    • 3000 years age Phoenician seamen found small mammals from Mediterrian and called the place “I-saphan-im” Island of the Hyrax. The Romans later modified the name to Hispania. That later became Spain. The animals were really rabbits! Not hyraxes, so the name “Spain” comes from faulty observation.
    Rock hyrax from Mt Kenya

    Related articles:

    ROCK HYRAX Procavia capensis

    Rock hyraxes of Mt Kenya

    Taita tree hyraxes filmed at night

    Acoustic communication of Taita tree hyrax

    Western tree hyrax – Dendrohyrax dorsalis

    Taita tree hyrax – mysterious relict species

    Key reference: Shoshani, J., Bloomer, P., Seiffert, E. (2013) ‘Order Hyracoidea – Hyraxes’ in Mammals of Africa. London, Bloomsbury, pp. 148-151.

    Other sources for Dendrohyraxes:

    Cordeiro, N.J. et al. (2005) ‘Notes on the ecology and status of some forest mammals in four Eastern Arc Mountains, Tanzania’, Journal of East African Natural History, 94(1), pp. 175–189. doi:10.2982/0012-8317(2005)94[175:NOTEAS]2.0.CO;2.

    Gaylard, A. and Kerley, G.I.H. (1997) ‘Diet of Tree Hyraxes Dendrohyrax arboreus (Hyracoidea: Procaviidae) in the Eastern Cape, South Africa’, Journal of Mammalogy, 78(1), pp. 213–221. doi:10.2307/1382654.

    Gaylard, A. and Kerley, G.I.H. (2001) ‘Habitat assessment for a rare, arboreal forest mammal, the tree hyrax (Dendrohyrax arboreus)’, African Journal of Ecology, 39(2), pp. 205–212. doi:10.1046/j.0141-6707.2000.301.x.

    Hoeck, H. (no date) ‘Some thoughts on the distribution of the tree hyraxes (genus Dendrohyrax) in Northern Tanzania’, 2017(13:47–49).

    IUCN (2013) ‘Dendrohyrax arboreus: Butynski, T., Hoeck, H. & de Jong, Y.A.: The IUCN Red List of Threatened Species 2015: e.T6409A21282806’. International Union for Conservation of Nature. doi:10.2305/IUCN.UK.2015-2.RLTS.T6409A21282806.en.

    IUCN (2014) ‘Dendrohyrax validus: Hoeck, H., Rovero, F., Cordeiro, N., Butynski, T., Perkin, A. & Jones, T.: The IUCN Red List of Threatened Species 2015: e.T136599A21288090’. International Union for Conservation of Nature. doi:10.2305/IUCN.UK.2015-2.RLTS.T136599A21288090.en.

    Kundaeli, J.N. (1976) ‘Distribution of tree hyrax (Dendrohyrax validus validus True) on Mt Kilimanjaro, Tanzania’, African Journal of Ecology, 14(4), pp. 253–264. doi:10.1111/j.1365-2028.1976.tb00241.x.

    Milner, J.M. and Harris, S. (1999) ‘Habitat use and ranging behaviour of tree hyrax, Dendrohyrax arboreus, in the Virunga Volcanoes, Rwanda: Habitat use by tree hyrax’, African Journal of Ecology, 37(3), pp. 281–294. doi:10.1046/j.1365-2028.1999.00185.x.

    Oates, J.F. et al. (2021) ‘A new species of tree hyrax (Procaviidae: (Dendrohyrax) from West Africa and the significance of the Niger–Volta interfluvium in mammalian biogeography’, Zoological Journal of the Linnean Society, p. zlab029. doi:10.1093/zoolinnean/zlab029.

    Opperman, E.J., Cherry, M.I. and Makunga, N.P. (2018) ‘Community harvesting of trees used as dens and for food by the tree hyrax (Dendrohyrax arboreus) in the Pirie forest, South Africa’, Koedoe, 60(1). doi:10.4102/koedoe.v60i1.1481.

    Roberts, D., Topp-Jørgensen, E. and Moyer, D. (2013) ‘Dendrohyrax validus Eastern tree hyrax’, in Mammals of Africa. London, Bloomsbury, pp. 158–161.

    Topp-Jørgensen, J.E. et al. (2008) ‘Quantifying the Response of Tree Hyraxes ( Dendrohyrax Validus ) to Human Disturbance in the Udzungwa Mountains, Tanzania’, Tropical Conservation Science, 1(1), pp. 63–74. doi:10.1177/194008290800100106.

    True, F.W. (1890) ‘Description of two new species of mammals from Mt. Kilima-Njaro, East Africa’, Proceedings of the United States National Museum, 13(814), pp. 227–229. doi:10.5479/si.00963801.814.227.

  • ROCK HYRAX Procavia capensis

    ROCK HYRAX Procavia capensis

    According to Mammals of Africa (MOA) 2013 17 subspecies are recognized. However, many of these subspecies have been elevated to level of distinct species.

    Rock hyraxes in Mt Kenya. These rock hyraxes live in the altitude of 4300 m asl. Many people climbing to Mt Kenya are first startled by their loud calls that seem to be coming from nowhere.

    Rock hyraxes have wide distribution in Africa and in many countries in Middle East

    Distribution of Rock hyrax (Map from wikipedia https://en.wikipedia.org/wiki/Rock_hyrax)

    IUCN assessment of rock hyrax

    IUCN status Least Consern LC

    Rock hyraxes are dependent on rocky outcrops, mountain cliffs or boulders that provide shelter for them.

    From sea level to 4300m asl in Mt Kenya

    Rock hyraxes are diurnal group living animals. One group may have even 80 individuals.

    More than 90 % of the day is spent resting.

    They feed on grasses, buds, fruits, berries.

    Huddling behavior is most common interaction. During warmer times rock hyraxes may rest alone.

    Rock hyraxes are highly vocal. Fourie (1977) recorded 21 vocal sound and 4 non-vocal sounds.

    Rock hyraxes from Mt Kenya

    Rock hyraxes singing songs, witch is rare phenomenon among mammals (Koren 2006, Koren & Geffren 2009, Demartsev et al. 2014). In rock hyraxes songs are sang by males. Most complicated and powerful songs are sang by strong males. These songs are most likely individual badges that males use to advertise their fitness to females.

    With one breeding season, all females give birth to 1-4 within three weeks.

    Weaning occurs within 1-5 months. Both sexes reach maturity at 28-29 months.

    Allthough some habitats remain always occupied, in many locations rock hyraxes colonies may dissapear and then reappear according to metapopulation theory.

    In some counties e.g. Saudi-Arabia rock hyraxes are hunted for sport, meat and skins.

    Rock hyraxes from Plzen Zoo, Czech

    How do you recognize hyrax species from one another?

    If they are diurnal, they are either rock hyraxes or bush hyraxes. These are quite different form their appearance.

    If they are nocturnal, they are tree hyraxes. Tree hyraxes are usually seen in the proximity of trees as they only eat leaves. In West Africa they are D. dorsalis or D. interfluvialis. They can be separated by their calls. Most common tree hyrax is Dendrohyrax arboreus. This species can be found from equator to South Africa. Other tree hyraxes D. validus and Taita tree hyrax sound very different. D. arboreus sounds like halloween sound track. D. validus has simple hac calls and Taita tree hyraxes have strangled thwack as their main contact calls. You can listen to Taita tree hyrax from here

    Key reference: Hoeck, H. Bloomer, P. (2013) ´Procavia capensis Rock hyrax (Klipdassie)’. In “Mammals of Africa” Vol 1. London Bloomsbury. pages 166-171

    Demartsev, V. et al. (2014) ‘Male hyraxes increase song complexity and duration in the presence of alert individuals’, Behavioral Ecology, 25(6), pp. 1451–1458. doi:10.1093/beheco/aru155.

    Butynski, T., Hoeck, H., Koren, L. & de Jong, Y.A. 2015. Procavia capensis. The IUCN Red List of
    Threatened Species 2015: e.T41766A21285876. http://dx.doi.org/10.2305/IUCN.UK.2015-
    2.RLTS.T41766A21285876.en

    Koren, L. (2006) Vocalization as an indicator of individual quality in the rock hyrax. PhD-thesis, Tel-Aviv University.

    Koren, L. and Geffen, E. (2009) ‘Complex call in male rock hyrax (Procavia capensis): a multi-information distributing channel’, Behavioral Ecology and Sociobiology, 63(4), pp. 581–590. doi:10.1007/s00265-008-0693-2.

    Oates, J.F. et al. (2021) ‘A new species of tree hyrax (Procaviidae: (Dendrohyrax) from West Africa and the significance of the Niger–Volta interfluvium in mammalian biogeography’, Zoological Journal of the Linnean Society, p. zlab029. doi:10.1093/zoolinnean/zlab029.