Spatial extent and consequences of black bass (Micropterus spp.) invasions in a Cape Floristic Region river basin

1. Black bass (Micropterus spp.) are invasive fish that have adversely affected native fish communities in many regions of the world. They are known to threaten native fishes in the Cape Floristic Region of South Africa, a fish endemism hotspot, but the extent of invasion and consistency of impacts at river basin scales are not known. 2. This study investigated the extent of black bass invasions in 41 tributaries in the Olifants–Doorn River basin (ODR) using above-water observations, snorkel surveys and underwater video assessment. Physical barriers that defined the upper limit of black bass distributions in tributaries were measured. Black bass impacts on the densities and diversity of the native fish fauna across the basin were assessed. 3. Black bass were found to have invaded 81% of stream habitat in the basin, with Micropterus dolomieu and Micropterus punctulatus consistently being blocked by physical barriers in the form of waterfalls, cascades and chutes. These barriers had a minimum height of 49 cm and a median height of 1.09 m. 4. Small-bodied cyprinid minnows (Barbus calidus and Pseudobarbus phlegethon) were consistently extirpated from black bass-occupied reaches, while larger cyprinid species co-occurred with black bass, but only when they were larger than 10 cm. 5. These findings demonstrate the severe habitat loss to native fishes as a result of black bass invasion, and the prevention of the further spread and removal of black bass from these rivers should be a high conservation priority. 6. The study demonstrates the critical role physical barriers play in preventing the extinction of native fish species and provides a basis for the planning of conservation interventions such as the construction of in-stream invasion barriers

Ectoparasite diversity on rodents at de Hoop Nature Reserve, Western Cape Province

Fleas, lice, mites and ticks were collected from 41 Rhabdomys pumilio and seven Otomys irroratus at De Hoop Nature Reserve in the Western Cape Province of South Africa. The aims of the study were firstly to quantify parasite abundance and to record the species richness on the rodents. Secondly to record the parasite species that were shared between R. pumilio and O. irroratus and thirdly to compare the parasite abundance on R. pumilio between localities of varying antelope activity. Each rodent was individually examined under a stereoscopic microscope and its parasites were removed, counted and identified to species level. The parasite species included seven flea, one louse, nine mite and 10 tick species. Three undescribed mite species were also recovered and new locality records were obtained for six flea, two lice, two mite and one tick species. Several flea, mite and tick species were shared between R. pumilio and O. irroratus. Both the mean abundance of the total ectoparasite burdens and the mean tick abundance were significantly higher on R. pumilio individuals that were trapped in habitats preferred and occupied by large antelope species compared to habitats in which antelope were absent or rarely present.Articl

Ectoparasite diversity on rodents at De Hoop Nature Reserve, Western Cape Province

Fleas, lice, mites and ticks were collected from 41 Rhabdomys pumilio and seven Otomys irroratus at De Hoop Nature Reserve in theWestern Cape Province of South Africa. The aims of the study were firstly to quantify parasite abundance and to record the species richness on the rodents. Secondly to record the parasite species that were shared between R. pumilio and O. irroratus and thirdly to compare the parasite abundance on R. pumilio between localities of varying antelope activity. Each rodent was individually examined under a stereoscopic microscope and its parasites were removed, counted and identified to species level. The parasite species included seven flea, one louse, nine mite and 10 tick species. Three undescribed mite species were also recovered and new locality records were obtained for six flea, two lice, two mite and one tick species. Several flea, mite and tick species were shared between R. pumilio and O. irroratus. Both the mean abundance of the total ectoparasite burdens and the mean tick abundance were significantly higher on R. pumilio individuals that were trapped in habitats preferred and occupied by large antelope species compared to habitats in which antelope were absent or rarely present

Ectoparasite diversity on rodents at De Hoop Nature Reserve, Western Cape Province

Fleas, lice, mites and ticks were collected from 41 Rhabdomys pumilio and seven Otomys irroratus at De Hoop Nature Reserve in theWestern Cape Province of South Africa. The aims of the study were firstly to quantify parasite abundance and to record the species richness on the rodents. Secondly to record the parasite species that were shared between R. pumilio and O. irroratus and thirdly to compare the parasite abundance on R. pumilio between localities of varying antelope activity. Each rodent was individually examined under a stereoscopic microscope and its parasites were removed, counted and identified to species level. The parasite species included seven flea, one louse, nine mite and 10 tick species. Three undescribed mite species were also recovered and new locality records were obtained for six flea, two lice, two mite and one tick species. Several flea, mite and tick species were shared between R. pumilio and O. irroratus. Both the mean abundance of the total ectoparasite burdens and the mean tick abundance were significantly higher on R. pumilio individuals that were trapped in habitats preferred and occupied by large antelope species compared to habitats in which antelope were absent or rarely present

Spatial patterns of large African cats: a large-scale study on density, home range size, and home range overlap of lions Panthera leo and leopards Panthera pardus

Environmental Biolog