Killing of Cape fur seal (Arctocephalus pusillus pusillus) pups by brown hyenas (Parahyaena brunnea) at mainland breeding colonies along the coastal Namib Desert

Abstract

Brown hyenas (Parahyaena brunnea) scavenge and kill seal pups at mainland Cape fur seal (Arctocephalus pusillus pusillus) colonies. The prey encounter interval and interval between kills depended on seal density, and increased density resulted in an increase of the capture rate and increase in hunting efficiency from 14% in November to 47% in January. The time brown hyenas spent at the seal colony decreased with increasing seal density and increasing air temperatures. Nevertheless, they were regularly active during the day when less adult seals were present at the colony, which indicates that the attendance of adult seals might play a role in the choice of foraging time. Brown hyenas killed seal pups throughout the study period. The predation rate was independent of the availability of non-violent mortalities, but the absolute number of kills was positively density-dependent. Mass kill events were recorded throughout the study period and are therefore not unusual occurrences. The overabundance of easy and vulnerable prey may lead to an over stimulus situation that triggers killing independent of the consumption of the prey or the hunger state.

High carnivore population density highlights the conservation value of industrialised sites

“…Private nature reserves created around the Venetia diamond mine in South Africa and the Jwaneng diamond mine in Botswana support a broad complement of large mammals including elephants ( Loxodonta africana ), African lions, leopards, cheetahs, African wild dogs ( Lycaon pictus ), brown hyaenas ( Hyaena brunnea ), and black-backed jackals ( Canis mesomelas ) 10 , 60 – 62 . The Sperrgebiet exclusion zone in Namibia, established to protect diamond deposits 59 , has now been proclaimed a National Park 63 . The consequent changes in the ecological functions of these human modified areas can produce a new combination of species, sometimes modifying and, in some cases, increasing the local richness 7 , 64 .…”

Evaluation of a Conflict-Related Brown Hyaena Translocation in Central Namibia

“…The predatory capacity of brown hyaenas (in areas with largely immobile prey) has been documented in detail (e.g. Wiesel, 2010) suggesting a strongly developed instinct for hunting live prey. In this case, examination of bite wounds provided evidence (subcutaneous haemorrhaging on hind quarters and hind legs coupled with only mild skin perforations and signs of tearing, dragging and pulling) that these were indeed atypical of other indigenous large predators, i.e.…”

Short Note: Observations from Video Footage of Red Fox (Vulpes vulpes) Activity Within a Grey Seal (Halichoerus grypus) Breeding Colony on the UK Mainland

“…Still, the observations presented herein illustrate the potential for close proximity of canids and pinnipeds at mainland breeding sites and, therefore, the potential for cross-species zoonoses, including rabies. & Baker, 1988North Rona 1959-196814.5-25.0% 19.2% Boyd & Campbell, 1971North Rona 1972--30.0%*^Summers et al, 1975North Rona 1997-1998 14.5%* Twiss et al, 2003Donna Nook 2001-2010 5.2-11.5% 9.0% Lidstone-Scott, unpub. data *Data not from the entire breeding colonŷ Pup mortality rate is an estimate…”

“…Arctic foxes (Alopex lagopus) have also been reported to predate on ringed seals, taking an average of 26.1% of the estimated pup production over a 3-y period (Smith, 1976). Where pinnipeds form mainland breeding colonies, terrestrial predators can also impact pup survival; for example, brown hyenas (Parahyaena brunnea) are known to take up to 9.6% of Cape fur seal (Arctocephalus pusillus pusillus) pups on mainland breeding colonies in Namibia, Africa (Wiesel, 2010).…”