Hundreds of Cape Fur seals entangled in fishing lines and nets every
year
Date:
August 20, 2021
Source:
Stellenbosch University
Summary:
Fishing line and nets are having a major impact on Cape fur seals,
the most common marine mammal observed around the coastline
of South Africa and Namibia, where they are endemic. The first
results from an ongoing study, initiated in 2018, shows that a
high number of affected animals are pups and juveniles, which
were mainly entangled around the neck with fishing line, causing
horrific injuries and resulting in a slow, painful death.
FULL STORY ========================================================================== Fishing line and nets are having a major impact on Cape fur seals (Arctocephalus pusillus pusillus), the most common marine mammal observed around the coastline of South Africa and Namibia, where they are endemic.
========================================================================== While their population numbers are considered healthy, plastic pollution,
and particularly fishing line and nets, are causing horrific injuries
and can result in a slow, painful death.
These are the first results from an ongoing project, initiated in 2018,
to investigate the impact of pollution on Cape fur seals in Namibia. The project involves researchers and conservationists from Stellenbosch
University, Sea Search-Namibian Dolphin Project and Ocean Conservation
Namibia.
The team monitors the entanglement rates of seals and Ocean Conservation Namibia have been disentangling many of the animals affected. The first
results from the project were published this week in the scientific
journal Marine Pollution Bulletin.
The study demonstrated that a high number of affected animals were pups
and juveniles, which were mainly entangled around the neck by fishing
line. Rates of entanglement were roughly 1 per 500 animals and was similar between the two colonies investigated at Walvis Bay and Cape Cross. Of
the 347 entangled animals documented, the disentanglement team, led by
Naude' Dreyer of Ocean Conservation Namibia, were able to successfully disentangled 191 individuals between 2018 and March 2020.
Working in Africa with limited recourses, the team also compared low cost methods of data collection. They found that photographic scans of the
colonies were a fast and accurate method to collect data on entangled individuals and the materials they are trapped in.
Dr Tess Gridley, co-director of the Namibia Dolphin Project and an extraordinary senior lecturer in the Department of Botany and Zoology
at Stellenbosch University, says plastic pollution and particularly
lost and discarded fishing nets are having a big impact to marine life:
"Once entangled, these seals face a very painful and uncertain future:
finding food becomes harder and wounds can become deep and debilitating,
and likely cause death in many cases. Changes to policy could help,
such as financial incentives to recover lines, safe disposal of
nets and sustainable alternatives to plastics." Stephanie Curtis,
a research student with the Namibian Dolphin Project and lead author,
says the impact of plastic pollution in the oceans is devastating:
"Seals should not have to suffer this way because of our carelessness
with waste." According to Dr Simon Elwen, co-director of the Namibian
Dolphin Project and also associated with SU's Department of Botany and
Zoology, fur seals are especially vulnerable to becoming entangled:
"They are very curious and playful animals and will investigate objects
in the water, but their thick, backwards facing fur which keeps them warm
at sea easily snags lines and straps and stops it falling back off."
Naude' Dreyer from Ocean Conservation Namibia says the project is
ongoing: "Since the start of 2021 we have already disentangled over
600 fur seals in only two colonies. This is the tip of the iceberg. It
is imperative that studies such as this highlight the consequences of
plastic waste on marine animals, and bring around change for the better." ========================================================================== Story Source: Materials provided by Stellenbosch_University. Note:
Content may be edited for style and length.
========================================================================== Journal Reference:
1. S. Curtis, S.H. Elwen, N. Dreyer, T. Gridley. Entanglement of
Cape fur
seals (Arctocephalus pusillus pusillus) at colonies in central
Namibia.
Marine Pollution Bulletin, 2021; 171: 112759 DOI: 10.1016/
j.marpolbul.2021.112759 ==========================================================================
Link to news story:
https://www.sciencedaily.com/releases/2021/08/210820111045.htm
--- up 15 weeks, 22 hours, 45 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)