Ring
Neck
By Ally McNaughton
This past summer, as I embarked on a research
cruise with the North Pacific Universities Marine Mammal Research Consortium
(NPUMMRC), I was prepared for
an amazing, once-in-a-lifetime experience. We would be visiting remote
Steller sea lion haul-outs and rookeries along Hecate Strait and around
the scenic Queen Charlotte Islands, counting animals at each site, sighting
branded and tagged individuals, and collecting scat for dietary analysis.
As we explored some of the most pristine
areas of the B.C. coast, I was struck – as expected – by the
picturesque beauty and rugged expanse of our coast. What I was not prepared
for, however, was my introduction to ring-necks.
 A
Ring-neck refers to a sea lion that has swum into and become entangled
in a small piece of netting, rope or strap. One of the largest sources
of ring-neck appears to be plastic packing straps, the kind that firmly
keeps the lid on boxes of fishing bait. Once the plastic strap slides
over the head and onto the neck of the animal, it remains there until
they die; the animal cannot free itself. The straps are designed to resist
tensile stress and cannot be pulled apart by a scratching flipper. To
become a ring-neck is to die a slow and painful death by starvation, infection,
or asphyxiation.
“The strap cuts farther into the
neck as the sea lion grows, causing an infection that is obvious by the
discolouration of the fur along the neck,” explained Andrew Trites,
NPUMMRC Research Director, as he showed me my first ring-neck (pictured
above). “Judging by the degree of emaciation, this animal will die
within the year.”
We also encountered sea lions that had
swallowed hooks and lines, which cause severe internal cuts and infections.
Each time it was difficult to deal with the helplessness we felt: even
though we are sea lion experts, there was nothing we could do to help
them. We could not possibly get close enough to cut the strap away, and
any attempt to dart the animal with a tranquilizer might spook it into
the water, which is a deadly place for a tranquilizer to take effect.
Our hands, like their necks, were tied.
The incidence of ring-neck — although
not yet estimated — is believed to be low and not epidemic among
sea lions. But the Western Alaskan population of Steller sea lions is
faced with going extinct for unknown reasons, and additional stresses
like entanglement can only aggravate their situation. In a population
this small, the survival of every individual makes a difference.
If experts like us cannot even help these
afflicted animals, efforts must focus on preventing the problem in the
first place.  Solutions
do exist: international shoreline cleanups remove thousands of tonnes
of potential marine litter each year, while special hard-to-swallow circle
hooks are vastly reducing the number of sea turtles accidentally killed
in some commercial fisheries. Can these hooks be used in B.C. and Alaskan
fisheries? Can the glue that binds packing straps be designed to degrade
over time? Could small refinements in these technologies help to save
lives?
As scientists, we observe sea lions in
their natural habitat, but human influence in that habitat has become
abundantly clear in recent decades. Scientists cannot solve the entanglement
problem alone, but we can call attention to this issue and advocate solutions
on behalf of those without a voice.
8 February 2006
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