Monday, July 08, 2013

Seals lost - Can they be found?

The Case of the Caribbean Monk Seal 

Caribbean monk seal range map
U.S. Government map of the former range of the Carribean monk seal

Mammals have invaded the sea many times. The sea otters made themselves mostly at home,and  the sea mink was doing fine until humans exterminated it. The sirenians, the manatees and dugongs, are threatened but not yet in dire straits, unless you count Steller's sea cow, which lasted only a few decades after humans found it.  The cetaceans have produced some 70 living species, and the pinnipeds - the seals and sea lions – were mostly doing all right about a century ago despite longtime hunting of some species. 
Now the Mediterranean monk seal has been driven to the edge, its Hawaiian cousin is threatened (why do these close relatives live so far apart? No one knows), and the Caribbean monk seal is - well - is it extinct?
In my first book, I wrote hopefully of Monachus tropicalis and its chances for survival.  In my second, I was still hopeful. Now... ugh.
The monk seal was the only pinniped endemic to the Caribbean, and the first New World mammal recorded by Christopher Columbus.  Columbus’ men killed eight of the abundant, large (up to 200 kg or more), curious animals they called “sea wolves.”   Unfortunately, other humans found them vulnerable too.  (Homo sapiens is not coming off well in this article.)
In 1911, the last large colony – about 200 seals on islands off Yucatan – was slaughtered.  A lone individual was killed near Key West, Florida, in 1933.  A small group of seals on islands off Jamaica was observed until the early 1950s, but vanished.  Except for scattered individual sightings, that was it, seemingly. The U.S. government, for one, lists no confirmed sightings after 1952.
In 1997, the last major survey effort was carried out. It offered some renewed hope. When 93  Haitian and Jamaican fishermen were interviewed about marine mammals, 21 included the monk seal, and 16  said they’d seen one within the last two years.  
Since then, however, there’s been nothing. The U.S. dropped it from the Endangered Species List in 2008 due to extinction. It’s been suggested some reports of Caribbean monk seals could be caused by California sea lions (Zalophus califonianus) from oceanic parks along Florida’s Gulf Coast. California sea lions are normally darker than monk seals, but their size ranges overlap, and the two could certainly be confused at a distance.  Some sightings may involve wayward members of other species.
Must we definitely close the file? Well, we do have the example of the Galapagos fur seal. This animal was thought extinct not once but twice.  Its habitat was more remote, though. Traffic in the Caribbean is far higher than in the monk seal's abbreviated heyday. The IUCN agrees we've lost the species, and the hope based on the 1997 survey has pretty well evaporated.
I usually write this blog to talk about new discoveries or animals that have been, or may be, rediscovered. Today, though, I'm writing my personal obituary for the Caribbean monk seal.  I don't think we'll see it again. The best way to honor its passing is to save its fellow seals and sea lions - while we still can.  


Adam, Peter, and Gabriela Garcia. 2003. “New information on the natural history, distribution, and skull size of the extinct (?) West Indian Monk Seal, Monachus tropicalis,” Marine Mammal Science, 19:2, p.297.
Boyd, I.L., and M.P. Stanfield.  1998.  “Circumstantial evidence for the presence of monk seals in the West Indies,” Oryx, 32, p.310.
The Monachus Guardian (on-line journal) (2),
Rice, Dale. 1998.  Marine Mammals of the World.  Lawrence, KS: The Society for Marine Mammology.
Swanson, Gail.  2000.  “Final Millennium for the Caribbean Monk Seal,” The Monachus Guardian 3(1),
Walters, Mark.  1997.  “Ghost of a Monk Seal,” Animals, November/December, p.23.


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