Here's that information on the Riverine Rabbit - enjoy :)
Andrea
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The Riverine Rabbit -
Bunolagus monticularis
There are many endangered species
of animal and plant in South Africa, but none of the country’s mammals are as
endangered as the riverine rabbit (Smithers & Apps
2000), also known as the “bushman
hare”, “doekvoetjie” or “boshaas” (Collins
2001; ARKive 2007). The IUCN Red Data List
classified the riverine rabbit as Critically Endangered in 2004 (ARKive 2007;
IUCN 2011) due to a constantly decreasing population (IUCN 2011). Although there seem to be more individuals than
previously thought (Stuart 2007), it cannot be denied that this is still a
pressing issue.
Physical
Description
The riverine rabbit is
distinctive in appearance (see Appendix A, Figure 1). Usually grey-brown in
colour, it stands at about 12cm tall (Butchart 2009) and has a “dark brown
stripe down the side of the lower jaw extending to ear base” which is unique to
the species (Stuart 2007) and a light-coloured ring around its eyes (ARKive
2007). Although it’s long ears may be deceiving, the rabbit can be
distinguished from a hare by its uniformly brown tail, as those of hares tend
to be black and white (Collins 2001). It also has long, thick fur (ARKive 2007;
Butchart 2009).
Behaviour
Although little seems to
be known about the riverine rabbit’s behaviour (Stuart 2007), what is known is
imperative to understanding the reasons for its precarious future. They are
solitary, nocturnal animals that lie during the day in shallow, dug-out burrows
(called forms) amongst the shrubs of which its habitat consists (Smithers &
Apps 2000; Collins 2001; ARKive 2007; Butchart 2009; IUCN 2011). They feed on
the leaves of shrubs and fresh grasses (Smithers & Apps 2000; Collins 2001;
ARKive 2007; Stuart 2007; Butchart 2009). They also practice coprophagia – the
eating of droppings – in order to gain necessary vitamins and digestive
bacteria as efficiently as possible (Collins 2001; ARKive 2007).
Reproductively, the riverine rabbit is not as productive as most rabbits – they
only produce one litter of one to two young a year (Smithers & Apps 2000;
Collins 2001; ARKive 2007; Stuart 2007; IUCN 2011). These are born into
fur-lined forms (Smithers & Apps 2000; ARKive 2007; Stuart 2007). Natural
predators include cats and genets (Butchart 2009).
Distribution
Bunolagus
monticularis has a very limited distribution (see Appendix A, Figure 2). Itexists
only in the Karoo region of South Africa, to which it is endemic, i.e. it is
found nowhere else in the world (ARKive
2007; Stuart 2007; Butchart 2009). Riverine rabbits
exist in the habitat that their name suggests - it is only found in the
riverine vegetation along seasonal rivers in dry areas (Smithers & Apps
2000; Collins 2001; ARKive 2007; Stuart 2007; Butchart 2009; IUCN 2011). These areas
consist of low, dense, moist and succulent scrubland and grasses (IUCN 2011).
Statistical Data
IUCN (2011) states that
“the current population is estimated at less than 250 breeding pairs and is
declining”, and that “there has been a rapid decline of population due to loss
of 50-60% of habitat in the past 70 years”. There seem to be no more than 50
individuals in each subpopulation (individuals living in close proximity to one
another). The historical habitat has been estimated to have decreased by 51-81%
in the last 100 years, and the current habitat is predicted to decline by about
20% in the next century. (IUCN 2011)
Why
is it endangered?
The decline in population
numbers can be linked to an increase in agricultural activity (Smithers &
Apps 2000; Collins 2001; ARKive 2007; Stuart 2007; Butchart 2009; IUCN 2011).
Cultivation and livestock farming gives rise to extensive ploughing that
destroys the rabbit’s habitat (Smithers & Apps 2000; Collins 2001; ARKive
2007; IUCN 2011), overgrazing that causes erosion, depleting food sources and
cover to hide from predators (Collins 2001; ARKive 2007), fencing that
restricts movement and scatters individuals (IUCN 2011). Agriculture and
erosion means that individual rabbits are becoming more scattered (IUCN 2011),
and a scattered population means less breeding opportunities. The riverine
rabbit is also area-specific (which means that it is less likely to survive in
other, more generalised areas), and is therefore more sensitive to disturbance.
An increase in farming
activity also gives rise to an increase in domestic animals. This puts added
predatory pressure on the rabbit population (Smithers & Apps 2000) - like
all rabbits, the young are altricial, meaning that they are born blind and
helpless (ARKive 2007), and so are particularly vulnerable to predators, and
only producing one young a year means that they are not very successful
breeders. This makes them particularly sensitive to predator pressure, as they
cannot quickly reproduce to replace lost young.
The rabbits are also hunted for sport, and frequently are caught in
traps set by farmers for predators or pests (ARKive 2007; IUCN 2011).
Solutions
Attempts to breed the
animals in captivity and re-introduce them into their natural habitat are being
made (Collins 2001), but are largely unsuccessful (Smithers & Apps 2000).
Collins (2001) suggest that “the only
way to secure the long term survival of a species is to protect its natural
habitat”. Farmers are frequently encouraged to declare areas of their land Natural
Heritage Sites or conservancies (Collins 2001) in order to save the habitat of
the rabbits. Protection of said habitat also benefits the farmers in that the
vegetation prevents run-off and loss of topsoil and ground water (Collins
2001). So far, three conservancies exist in the Karoo (ARKive 2007). The Endangered Wildlife
Trust’s Riverine Rabbit Working Group was also created in 2003 “with the aim of
establishing and conserving an ecosystem and socioeconomic conditions in the
Karoo that can support a stable population of riverine rabbits” (ARKive 2007).
The riverine rabbit
population is undoubtedly under threat, and solutions are being sought out. Initiatives
like the above, as well as awareness projects, are imperative to the survival
of the riverine rabbit, otherwise, as the IUCN (2011) has predicted, “the
probability of extinction in the wild is more than 50% within the next 100
years” for the already critically endangered mammal.
ARKIVE. 2007. Riverine rabbit (Bunolagus monticularis). http://www.arkive.org/riverine-rabbit/bunolagus-monticularis/#text=All
BUTCHART, D. 2009. Wildlife of Southern Africa: A Photographic
Guide. Struik Nature, Cape Town.
COLLINS, J. 2001. Riverine Rabbit.
http://www.bcb.uwc.ac.za/envfacts/facts/riverine.htm
SMITHERS, R.H.N. &
APPS, P. 2000. Smithers’ Mammals of
Southern Africa: A Field Guide. Struik Publishers, Cape Town.
STUART, C. & STUART, T. 2007. Field Guide to Mammals of Southern Africa. Struik Nature, Cape Town.
