Warming oceans lead to more fur seal deaths from hookworm infection

Date:  November 6, 2018

Source:  eLife

Rising ocean temperatures are putting fur seal pups at greater risk of death from hookworm infections, according to new findings published in eLife.

The results shed new light on how warmer oceans can alter specific physiological processes in marine mammals, and suggest that infectious diseases could cause higher mortality rates if temperatures keep rising.

"Increasing ocean temperatures are associated with changes in the patterns of wind and ocean currents, which cause a decrease in the cycling of nutrients and, by extension, the abundance of life including fishes," says first author Mauricio Seguel, Postdoctoral Associate in the Odum School of Ecology at the University of Georgia, Athens, US.

"Reductions in marine life have also been linked with the decline of marine mammal populations, as they rely on fish as their main food supply. Fur seals and sea lions may be included here, because although their pups live on land, they depend on their mother's' milk for survival, which can only be produced if the mothers eat enough fish."

To investigate how marine mammals may be affected by changes in ocean conditions, Seguel and his team studied the health and survival of a colony of fur seals in South America between 2004-2008 and 2012-2017. "As hookworm infection is a major cause of death in this group of animals, whereby the parasite gets into the intestine of seal pups and sucks their blood, we wanted to see if environmental change affects the pups' ability to respond to this parasite," Seguel explains.

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Australian fur seal pup population is shrinking

Long-term monitoring program effective in tracking seal populations over time

Date:  September 5, 2018

Source:  PLOS

A census of annual pup production by Australian fur seal populations revealed the first reduction since species-wide protection was implemented in 1975, according to a study published September 5 in the open-access journal PLOS ONE by Rebecca McIntosh of the Phillip Island Nature Parks in Victoria, Australia, and colleagues. The study also shows that the long-term monitoring program for the Australian fur seal has effectively tracked population trends over time.

In the marine environment, monitoring the abundance and population trends of a top predator can provide measures of ecosystem health and management success. Fur seals, Arctocephalus pusillus doriferus, are important upper trophic level predators that, in Australia, are a protected marine species facing specific challenges related to fisheries and aquaculture management, ecotourism, potential impacts on seabirds, and response planning for oil spills and other emergencies. For these reasons, it is important to obtain accurate information about their abundance and population changes. An ad-hoc monitoring program coordinated across multiple stakeholders conducted a range-wide census of live pups in the Austral summers of 2002, 2007 and 2013. In the new study, McIntosh and colleagues set out to assess whether the monitoring program for the Australian fur seal is achieving its goals of determining pup abundance and estimating population trends.

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Massive sea lion, fur seal hunting in the Patagonian coasts is altering Southern Atlantic Ocean ecosystems

Date: January 18, 2017

Source: Universidad de Barcelona

Sea lion hunting by the Europeans at the Atlantic coasts of South America -it started in the 19th Century and continued up to the second half of the 20th century in Argentina and Uruguay- changed its nutrition guidelines of these pinnipeds as well as the structure of the coastal trophic network, according to the studies by the team codirected by Lluís Cardona, from the Department of Evolutionary Biology, Ecology and Environmental Sciences and the Biodiversity Research Institute of the University of Barcelona (IRBio), and Enrique Crespo, from the Patagonian National Center and the National University of Patagonia (Argentina).

The results of this study are shown in two articles, published in the scientific journals Oecologia and Paleobiology, its co-authors being Fabiana Saporiti and Lisette Zenteno (UB-IRBio), and Damian G. Vales (Patagonian National Center), among others.

This research is one of the results of the project Efectes de l'explotació humana sobre depredadors apicals i l'estructura de la xarxa tròfica del Mar Argentí durant els darrers 6000 anys (Effects of human exploitation on apex predators and structure of the trophic network in the Argentinian sea over the last 6000 years), financially supported by BBVA Foundation and led by Professor Àlex Aguilar (UB-IRBio), head of the Research Group on Large Marine Vertebrates of the University of Barcelona.

A megafauna exploited by humans in all oceans

Hunting and fishing usually create a reduction in the abundance of bigger species. Therefore, megafauna is considered to be one of the most threatened compounds of biodiversity. Marine mammals are an essential element of megafauna in all oceans and they have been extremely exploited by humans. However, knowing about the effects of this exploitation on the functioning of food networks in marine ecosystems -a high complex structural framework- is still a hard challenge for the scientists due to the difficulty to perform manipulative experiments.

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Scent matters to fur seals

Date: August 12, 2015

Source: Universitaet Bielefeld

Summary: Antarctic fur seals have unique ‘scent profile’ to recognize their pups, scientists have found. Until now researchers thought voice recognition was mostly important for finding their young, but now it is proven that scent also plays a crucial part.

Researchers studying Antarctic fur seals have discovered their scent has a unique 'profile' which enables them to recognize their offspring and family members. Until now researchers thought voice recognition was mostly important for finding their young, but now it is proven that scent also plays a crucial part. The results are published in the journal the Proceedings of the National Academy of Sciences.

The sense of smell and an animal's scent is an important means of communication in the animal kingdom. This applies not only to social interactions, but also to territorial behaviour, recognizing kin and when selecting a mate. However, understanding communication by smell is very challenging because of the mixture of chemicals on an animal's skin -- it may be affected by hormones, the microbial flora, body condition and health, and environmental factors. A team of scientists from the Bielefeld University and British Antarctic Survey sampled the skin and fur from dozens of mothers and their pups from two different colonies on the breeding beaches at Bird Island Research Station near the sub Antarctic Island of South Georgia. They found the scent of mothers and pups had similar characteristics.

Continued ...

Seals discovered having sex with penguins

Things are heating up in the cold climes of the sub-Antarctic. On a remote, and mostly desolate island, seals have been caught engaging in an extreme form of sexual behaviour.

Specifically, they have been trying to have sex with penguins.

More than one fur seal has been caught in the act, on more than one occasion.

And it's all been captured on film, with details being published inthe journal Polar Biology.

Perhaps it is a release of sexual frustration

The sexual behaviour of the fur seals hasn't come as a complete shock to the scientists that recorded it.

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Antarctic fur seals breed where they were born

Scientists have discovered that female Antarctic fur seals have an uncanny ability to return to within a body length of where they were born when it's time to breed.

Even if they don't manage to get this close, the majority of females give birth to pups within 12 metres of where they themselves were born.
'It's as if they have some sort of in-built GPS system,' says Dr Joe Hoffman from the University of Bielefeld in Germany, who led the study. 'Or it could be simply that they're using cues, like smell, that we can't measure. What is remarkable is that the colony is featureless, so it's impressive they find their way back.'
What's also striking is that these seals may have spent up to five years feeding hundreds of kilometres out at sea before coming home.
Knowing more about how these seals live their lives will help scientists understand how populations affect the fragile local ecosystem of South Georgia in the south Atlantic Ocean.

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Namibia's seals are worth more alive than dead

Seal slaughter is damaging Namibia's economy, says study
September 2011: Namibian fur seals are slaughtered in their thousands each year, but now a new economic study has confirmed the seals are worth three times as much alive rather than dead.

Comparing the latest figures for the seal trade and seal watching, the report says that the annual Namibian seal slaughter poses a major risk to the far more lucrative seal watching tourism industry.

Pelts can fetch less than £4Each year in Namibia, nursing baby seals are forcibly separated from their mothers and beaten and stabbed to death for their fur. Their pelts are sold for less than £4 each. Seal watching takes place on the very same beaches where the killing is allowed: Cape Cross, Atlas Bay and Wolf Bay. During the hunt season, from July 1 to November 15, hundreds of baby seals are clubbed to death between dawn and 8am at Cape Cross, a seal reserve.

At 10am, the same beach opens as a seal-watching attraction and hundreds of tourists flood in, oblivious to the carnage that took place just hours earlier.

The report, produced by the Australia-based independent economics consultancy Economists at Large, reveals that in 2008, the seal hunt generated only £320,000, a poor comparison to seal watching which netted £1.3 million in direct tourism expenditure in the same period.

Culling threatens lucrative tourist industryIt gives a detailed insight into the seal slaughter by examining the monetary benefits attached to each part of the trade. Bull seals account for a large proportion of the profits attached to the seal kills, as their penises are sold in Asian markets for alleged aphrodisiac qualities, at about £85 per kilogram. Aside from the low income netted by the seal slaughter, the practice poses a real threat to the far more lucrative seal-watching industry; large scale killing could lead to a collapse of seal populations, as witnessed in the 1990s.

Seal watching in contrast is a popular tourism activity undertaken by around 10 per cent of tourists to Namibia - just over 100,000 in 2008. Based on current growth trends, the report predicts that by 2016 as many as 175,000 tourists will participate in seal watching, generating close £2.2 million in direct revenues. Seal watching also delivers benefits to a far wider range of Namibian society than seal killing, helping boost tourism support services such as hotels and restaurants.

Call on Namibia to end slaughterMark Jones, executive director of Humane Society International UK, one of a group of organisation's that commissioned the report, said: ‘The Namibian authorities have long defended the seal slaughter on the grounds that it generates money and jobs, but this report shows that it could actually be damaging to the economy.

‘We call upon the government of Namibia to end the cruel slaughter of baby seals for their fur, and act in the best interest of its citizens and the seals, by promoting seal watching as a viable and sustainable economic alternative.'

Claire Bass, WSPA Interbational Oceans Campaign Leader, said: ‘ Each year up to 85,000 seals are killed in Namibia to make just a few dollars from their furs; this report highlights that they would be worth so much more to the Namibian economy alive.

‘Eco-tourism is a growing part of Namibia's identity but tourists will be shocked to find that a seal they photograph one day may be killed the next morning. There is a clear economic case for the government to protect these animals.'

http://www.wildlifeextra.com/go/news/seals-namibia.html

23 rare New Zealand fur seals clubbed to death at Kaikoura

Ohau Point fur seals killed

December 2010. 23 rare New Zealand fur seals have been found clubbed to death at a popular tourist viewing spot at Ohau Point near Kaikoura. New Zealand fur seals are a threatened species, protected under the Marine Mammal Protection Act. They were previously almost wiped out by commercial sealing and have now only recovered in a fraction of their former range.

The Ohau Point fur seal colony is one of Kaikoura's leading tourist attractions, where people can safely experience wild animals from the roadside. Tourism contributes heavily to the Kaikoura economy.

Independent conservation organisation Forest & Bird is disgusted and disappointed by the brutal killings.

"The deliberate killing of our wildlife is disgusting and the people of Kaikoura and New Zealand will be outraged," said Forest & Bird Marine Conservation Advocate Kirstie Knowles. "Everyone will condemn these stupid and cruel attacks."

Forest & Bird is supporting Department of Conservation pleas for anyone with information about the cowardly attacks to come forward.

http://www.wildlifeextra.com/go/news/fur-seals-ohau.html