Status and habitat description of the globally threatened Udzungwa Forest Partridge Xenoperdix udzungwensis thirty years after discovery

Summary The Udzungwa Forest Partridge Xenoperdix udzungwensis was discovered in 1991 in the geologically old and eco-climatically stable Udzungwa Mountains (hereafter the Udzungwas) in Tanzania - a global biodiversity hotspot in the Eastern Arc Mountains of East Africa. The partridge is categorised as globally ‘Endangered’ and this study aims at assessing its population status and habitat requirements in the two separate montane forests where it was discovered c.30 years ago and for the first time using systematic playback technique. We estimate the partridge population at c.2,800 individuals (1,680–3,860) confined to less than 150 km2 and now confined to a single forest and with a clearly declining distribution within the last few decades since its discovery. The species is confined to evergreen closed (semi-closed) canopy forest habitat with leaf litter and sedges on the forest floor for feeding and cover. The partridge has become an emblem for the high concentration of endemic species of the Udzungwa Mountains National Park. At the same time there is a risk that this species could go extinct without notice if the Tanzanian authorities do not tackle two envisaged main drivers, namely fragmentation of the evergreen forest area over the last few centuries and current illegal hunting. Hence it seems crucial to allow natural expansion of its forest habitat in the Udzungwas and to eliminate hunting in the other forest within its recently known distribution where the population has presumably been extirpated. The partridge is remarkable as its closest relatives are in South-east Asia and it is used as a flagship species for the Udzungwas, which has one of the highest concentrations of endemic species on earth.

Social Organisation, Ecology and Reproduction in the Sanje Mangabey (Cercocebus Sanjei) in the Udzungwa Mountains National Park, Tanzania

<p>Understanding of the biology of threatened species is central to effective planning for sustainable management of wildlife. The Sanje mangabey, Cercocebus sanjei of Udzungwa Mountains National Park in Tanzania is under pressure from increasinghuman hunting, and habitat loss threatens its long-term survival. This thesis endeavoured to document the socio-biological and ecological aspects of this little-known species in a small habituated group of 62 individuals within the Mwanihana forest in Udzungwa Mountains National Park. I studied the social organisation, size and age-sex composition of one group by following and monitoring of the Sanje mangabeys over a six-month period. I also investigated the spatial-temporal interactions and associations between age and sex classes within a group. I assessed the Sanje mangabey's ranging and movementpatterns and monitored its reproductive behaviour by examining female sexual skin swellings and relationships between sexual swellings and sexual behaviour. Further, I investigated the species feeding habits and influences of seasonal parameters (rainfall and temperature) upon reproduction, feeding ecology and behaviour of this species. The Sanje mangabey social organisation is structured in a hierarchy characterised by dominance according to the sex and age of individuals. The study group was composed of individuals of all sexes and age classes; newborn babies, juveniles, sub adults and adults, males and females. Adult males were generally dominant overfemales and males of lower age. Males showed more agonistic behaviours to juveniles than did females and there were stable linear dominance hierarchies among individuals across the sexes (Landau's dominance index, h' =0.92, p =0.0281) and a high directional consistency index, DC =0.91) for both sexes. The linearity indices 'h' were 0.84, P= 0.041, DC = 0.94 and 0.93, P = 0.0382, DC = 0.94) for males and females, respectively. Individuals spent about 8% on average of day grooming each other and the rate of grooming differed across and within sexes and age classes. There was a significant relationship between duration of the initiator's first grooming episode and subsequent reciprocation by the receiver in all age classes (P < 0.05). The independent effects of total grooming duration of the initiator also showed a significant difference and predicted total grooming duration of the recipient (P =0.0001). However, there was no evidence for grooming to be directed towards higher ranking Sanje mangabeys. The Sanje mangabey's home range was 301 hectares and exhibited a mean daily range of 1760 metres within the Mwanihana forest. The rangeand movement patterns of this species differed significantly between seasons of the year. During the dry season (no rain) the group covered larger distances (P = 0.001) between forest patches and moved significantly faster (P = 0.001) than during wet (rain) season. The Sanje mangabey is omnivorous, feeding on plant material, invertebrates and vertebrates such as lizards. There were marked influences of temperature and rainfall on the feeding patterns. Mangabeys utilised the arboreal layer (>16m high) during cool and wet periods and were observed feeding mostly on the ground resources during hot and dry periods. The reproductive potential and social behaviour of theSanje mangabey, however, did not vary with the different seasons of the year. Sanje mangabeys have a mean swelling cycle length of 32.1 +/- 2.4 days. Individual females showed differences in swelling duration (F =12.43, P = 0.043) and noevidence of group variation in cycle length (H= 30.2, DF = 6, P < 0.05) was seen. Maximum swelling lasted for 4.4 +/- 0.9 days on average and detumescence was 14.7 +/- 3.9 days. The mean menses length was 3 +/- 0.2 days (n = 3). Most cycling females, showed days with regular swellings of both sizes. The gestation length averaged 173days and the interval between birth and resumption of the swelling cycle was observed to be 184 days. The sexual skin swellings appear to be sexually attractive signals of female reproductive condition. Although mating occurred in all stages of the female cycle, a peak was observed during maximum swelling size and breakdown. These findings illustrate the utility of sex swellings as signals used by males to determine reproductive condition.</p>

Social Organisation, Ecology and Reproduction in the Sanje Mangabey (Cercocebus Sanjei) in the Udzungwa Mountains National Park, Tanzania

<p>Understanding of the biology of threatened species is central to effective planning for sustainable management of wildlife. The Sanje mangabey, Cercocebus sanjei of Udzungwa Mountains National Park in Tanzania is under pressure from increasinghuman hunting, and habitat loss threatens its long-term survival. This thesis endeavoured to document the socio-biological and ecological aspects of this little-known species in a small habituated group of 62 individuals within the Mwanihana forest in Udzungwa Mountains National Park. I studied the social organisation, size and age-sex composition of one group by following and monitoring of the Sanje mangabeys over a six-month period. I also investigated the spatial-temporal interactions and associations between age and sex classes within a group. I assessed the Sanje mangabey's ranging and movementpatterns and monitored its reproductive behaviour by examining female sexual skin swellings and relationships between sexual swellings and sexual behaviour. Further, I investigated the species feeding habits and influences of seasonal parameters (rainfall and temperature) upon reproduction, feeding ecology and behaviour of this species. The Sanje mangabey social organisation is structured in a hierarchy characterised by dominance according to the sex and age of individuals. The study group was composed of individuals of all sexes and age classes; newborn babies, juveniles, sub adults and adults, males and females. Adult males were generally dominant overfemales and males of lower age. Males showed more agonistic behaviours to juveniles than did females and there were stable linear dominance hierarchies among individuals across the sexes (Landau's dominance index, h' =0.92, p =0.0281) and a high directional consistency index, DC =0.91) for both sexes. The linearity indices 'h' were 0.84, P= 0.041, DC = 0.94 and 0.93, P = 0.0382, DC = 0.94) for males and females, respectively. Individuals spent about 8% on average of day grooming each other and the rate of grooming differed across and within sexes and age classes. There was a significant relationship between duration of the initiator's first grooming episode and subsequent reciprocation by the receiver in all age classes (P < 0.05). The independent effects of total grooming duration of the initiator also showed a significant difference and predicted total grooming duration of the recipient (P =0.0001). However, there was no evidence for grooming to be directed towards higher ranking Sanje mangabeys. The Sanje mangabey's home range was 301 hectares and exhibited a mean daily range of 1760 metres within the Mwanihana forest. The rangeand movement patterns of this species differed significantly between seasons of the year. During the dry season (no rain) the group covered larger distances (P = 0.001) between forest patches and moved significantly faster (P = 0.001) than during wet (rain) season. The Sanje mangabey is omnivorous, feeding on plant material, invertebrates and vertebrates such as lizards. There were marked influences of temperature and rainfall on the feeding patterns. Mangabeys utilised the arboreal layer (>16m high) during cool and wet periods and were observed feeding mostly on the ground resources during hot and dry periods. The reproductive potential and social behaviour of theSanje mangabey, however, did not vary with the different seasons of the year. Sanje mangabeys have a mean swelling cycle length of 32.1 +/- 2.4 days. Individual females showed differences in swelling duration (F =12.43, P = 0.043) and noevidence of group variation in cycle length (H= 30.2, DF = 6, P < 0.05) was seen. Maximum swelling lasted for 4.4 +/- 0.9 days on average and detumescence was 14.7 +/- 3.9 days. The mean menses length was 3 +/- 0.2 days (n = 3). Most cycling females, showed days with regular swellings of both sizes. The gestation length averaged 173days and the interval between birth and resumption of the swelling cycle was observed to be 184 days. The sexual skin swellings appear to be sexually attractive signals of female reproductive condition. Although mating occurred in all stages of the female cycle, a peak was observed during maximum swelling size and breakdown. These findings illustrate the utility of sex swellings as signals used by males to determine reproductive condition.</p>

Local Habitat Characteristics Determine Butterfly Diversity and Community Structure in a Threatened Kihansi Gorge Forest, Southern Udzungwa Mountains, Tanzania

Background Many species inhabiting Kihansi gorge ecosystem in Southern Udzungwa mountains, Tanzania are threatened with extinction due to habitat loss caused by constructed hydropower plant that diverted over 90% of the water off the Kihansi River. Understanding ecological correlates and structure of an animal community in perturbed ecosystems is an important way to enhancing species conservation particularly in this system where several species are already threatened with extinction. This study assessed influences of local habitat characteristics on the butterfly abundance, species richness and diversity and examined how the butterfly community structures across three structurally heterogeneous habitats in the Kihansi gorge forest. Butterfly abundance data were collected using baited traps and measured environmental variables in the field where trapping occurred. To understand the diversity and butterfly richness, these parameters were computed under Primer software. Non-metric multidimensional scaling and analysis of community similarity were used to analyse the butterfly community structure. Further, the generalized linear models were used to assess how the measured variables explained observed species diversity, abundance, and richness. Results In total, 72 species of butterfly in five families were recorded. Butterfly, species diversity and richness did not vary across the habitat types or elevation gradient but showed strong correlation with some habitat characteristics. Also, there was evidence of butterfly communities structuring into distinct groups that showed greater separation associated with the habitat characteristics they utilise. Further, across the study area, butterfly species diversity was mostly likely to increase in high canopy and in trees with smaller diameter at breast height and at lower ground cover. Similarly, abundance significantly increased in the woodland and wooded grassland habitats, where there was high canopy and where tree density was high. Furthermore, butterfly species richness was strongly positively associated with high canopy cover and was mostly likely to increase in sites closer to water source. Conclusion Assessing habitat correlates of the butterfly communities provide important information on what components of the habitats are most useful to target when planning conservation especially in threatened ecosystems. This also helps to reveal existing gaps in important knowledge that would be useful to improving long-term monitoring of biodiversity in in fragile systems such as the Kihansi gorge forest.

Revision of Dendrochilus (Coleoptera, Scolytinae)—with description of two new species from Tanzania

The genus Dendrochilus Schedl, 1963 is revised. Two new species are described from the Udzungwa Mountains in Tanzania. Dendrochilus tener sp. nov., and D. udzungwae sp. nov. are closely related with few morphological differences but are clearly separated by molecular data from four gene fragments. Together with the type species D. strombosiopsis Schedl, 1957 from Congo, the genus now includes three species. An identification key to species is provided.

Trophobiosis between a new species of Williamsrhizoecus (Hemiptera: Coccomorpha: Rhizoecidae) and Acropyga silvestrii (Hymenoptera: Formicidae) in Tanzania

A new myrmecophilous species of root mealybug, Williamsrhizoecus udzungwensis sp. n., is described from individuals found living within a nest of Acropyga silvestrii in the Udzungwa Mountains of Tanzania. Acropyga ants are highly specialized, obligate associates of scale insects, typically members of the scale family Xenococcidae. Acropyga are best known for vertically transmitting trophobiotic partners during their nuptial flights and for housing them within brood chambers. This article presents the first record of trophobiosis between a species of Williamsrhizoecus and Acropyga, and only the second record of an association between Acropyga and rhizoecids in the Old World. This discovery contributes important information about the few species of Rhizoecidae confirmed to engage in these unique symbioses, each putatively the result of a past horizontal transmission event from a xenococcid to a rhizoecid lineage. Included is a discussion on the diagnosis of Williamsrhizoecus and an updated key to the species.

A mountain of millipedes IX: Species of the family Gomphodesmidae from the Udzungwa Mountains, Tanzania (Diplopoda, Polydesmida)

A new genus and six new species of the family Gomphodesmidae from the Udzungwa Mts are described, including Pogoro alopias Rosenmejer & Enghoff sp. nov., Pogoro siren Rosenmejer & Enghoff sp. nov., Pogoropsis prolixopes Rosenmejer & Enghoff gen. et sp. nov., Emphysemastix frampt Olsen & Enghoff sp. nov., Agrophogonus hamulus Olsen & Enghoff sp. nov., and Agrophogonus pusillokiellandi Olsen & Enghoff sp. nov. Emphysemastix dracarys Olsen & Enghoff sp. nov. from Iringa city is described. Descriptive notes are given for Pogoro scharffi Hoffman, 2005, and Agrophogonus mwanihana Hoffmann, 2005. General gomphodesmid gonopod morphology is described and illustrated. A key to Udzungwa gomphodesmids is presented, as well as revised keys to all species of Emphysemastix and Agrophogonus. All gomphodesmid species from the Udzungwa Mts are mapped.

New species of Mecopodinae (Orthoptera, Tettigoniidae) from Tanzania

New species of Mecopodinae are described from Tanzanian mountain ranges. These are Apteroscirtus densissimus n. sp. from the Nguru Mountains, Gymnoscirtus corifterus n. sp. from the Udzungwa Mountains Nationalpark and a new subspecies of Phyloscirtus cordipennis Karsch, P. c. spinosus n. ssp. from the Nguru Mountains. Data on habitat are provided.