Featured Research

from universities, journals, and other organizations

Survival of the Galapagos sea lion

Date:
June 29, 2013
Source:
Zoological Society of London
Summary:
The study shows that Galapagos sea lions (Zalophus wollebaeki) are more prone to starvation because of exposure to human influences like pets and pollution. These can impair the level of their immunity, making them less able to hunt and more likely to go hungry when food is scarce.

This is a Galapagos sea lion.
Credit: ZSL_Paddy Brock

Immune systems of endangered Galapagos sea lions are in overdrive because of harmful activity by people, reveal scientists from the Zoological Society of London (ZSL).

The study shows that Galapagos sea lions (Zalophus wollebaeki) are more prone to starvation because of exposure to human influences like pets and pollution. These can impair the level of their immunity, making them less able to hunt and more likely to go hungry when food is scarce.

This research is published June 28 in the journal PLOS ONE.

Conservationists spent more than eighteen months on the Islands of San Cristobal, which is inhabited by humans, and Santa Fe, where there are no humans, dogs, cats, mice or rats. They tagged 60 Galapagos sea lions from each island and monitored their behaviour and physiology.

ZSL's Institute of Zoology Director, Professor Tim Blackburn says: "We are increasingly aware of the threats of infectious diseases to wildlife around the world, from amphibians in the tropics to the birds in British gardens. It is worrying that we are now potentially seeing such threats to sea lions in the supposedly pristine wilderness of the Galapagos Islands."

ZSL's Dr. Paddy Brock, author on the paper, says: "A tell-tale sign of an unhealthy sea lion is a thinner than normal layer of blubber, which is what we saw in the sea lions on San Cristobal. This was all the more notable as we didn't notice these patterns in sea lions on Santa Fe, where they live without the presence of people or pets.

""The immune systems of San Cristobel sea lions were more active, perhaps indicating a threat of infectious disease, which could mean human activity is increasing the chance of potentially dangerous diseases emerging in the Galapagos sea lion," Dr Brock added.

Despite laws designed to protect the unique wildlife found on the Galapagos, pets are regularly imported to the islands, which increases the risk of new diseases arriving and spreading to local species. In addition, dumping of sewage into the bay on San Cristobal where the sea lions live may be increasing their exposure to germs and bacteria associated with humans.

ZSL, together with collaborators, will continue to address the threats faced by the Galapagos sea lion by carrying out further research into the methods driving the described patterns, such as the role that genetics plays in shaping them.


Story Source:

The above story is based on materials provided by Zoological Society of London. Note: Materials may be edited for content and length.


Journal Reference:

  1. Patrick M. Brock, Ailsa J. Hall, Simon J. Goodman, Marilyn Cruz, Karina Acevedo-Whitehouse. Immune Activity, Body Condition and Human-Associated Environmental Impacts in a Wild Marine Mammal. PLoS ONE, 2013; 8 (6): e67132 DOI: 10.1371/journal.pone.0067132

Cite This Page:

Zoological Society of London. "Survival of the Galapagos sea lion." ScienceDaily. ScienceDaily, 29 June 2013. <www.sciencedaily.com/releases/2013/06/130629164735.htm>.
Zoological Society of London. (2013, June 29). Survival of the Galapagos sea lion. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2013/06/130629164735.htm
Zoological Society of London. "Survival of the Galapagos sea lion." ScienceDaily. www.sciencedaily.com/releases/2013/06/130629164735.htm (accessed July 28, 2014).

Share This




More Plants & Animals News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Sea Turtle Hatchlings Emerge from Nest

Raw: Sea Turtle Hatchlings Emerge from Nest

AP (July 27, 2014) A live-streaming webcam catches loggerhead sea turtle hatchlings emerging from a nest in the Florida Keys. (July 27) Video provided by AP
Powered by NewsLook.com
Trees Could Save More Than 850 Lives Each Year

Trees Could Save More Than 850 Lives Each Year

Newsy (July 27, 2014) A national study conducted by the USDA Forest Service found that trees collectively save more than 850 lives on an annual basis. Video provided by Newsy
Powered by NewsLook.com
What's To Blame For Worst Ebola Outbreak In History?

What's To Blame For Worst Ebola Outbreak In History?

Newsy (July 27, 2014) A U.S. doctor has tested positive for the deadly Ebola virus, as the worst-ever outbreak continues to grow. Video provided by Newsy
Powered by NewsLook.com
The New York Times Backs Pot Legalization

The New York Times Backs Pot Legalization

Newsy (July 27, 2014) The New York Times has officially endorsed the legalization of marijuana, but why now, and to what end? Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins