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Most impressive information.  I bookmarked one of the sites and will save
this message in order to more thoroughly review all the information you
provided.  Thanks.

Lee

----- Original Message -----
From: Christian Gerzner <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, May 17, 2000 9:48 PM
Subject: Sea Snake bites


> Folks,
>
> I've done a bit of research on this. The text appearing below, in light
> of bandwidth, is often shortened. The URL's give the full text.
>
> Case 1:
>
> > Believed to be the first reported case of envenomation by  Astrotia
stokesii in Australia.  In October 1979, a two year old girl began screaming
while playing in the water at a beach 3km from Yeppoon, Queensland.
> The photograph illustrates the snake involved and the appearance of the
> child's foot, showing multiple bite marks suggestive of severe
envenomation.
> <http://www.pharmacology.unimelb.edu.au/pharmwww/avruweb/seasnak.htm>
>
> Case 2:
>
> > Using a custom-built aquarium at the Smithsonian Tropical Research
Institute, photographer Carl Hansen got this close-up view of deadly Yellow
Bellied Sea Snakes (Pelamis platurus). Captured for study by STRI
scientists, they have the most toxic venom of any snake. There is no known
antivenom for their bite.
> "Fortunately," says Hansen, "these snakes are not aggressive and rarely
> try to bite even if handled. They are highly modified for life in the
> open Pacific Ocean and are unable to crawl on land. They can often be
> seen floating along drift lines on the surface, but spend much of their
> time in deep dives."
> http://photo2.si.edu/different/dif_csnake.html
>
> Case 3:
>
> I couldn't copy the text on this site, some interesting observations
though.
> http://www.underwater.com.au/seasnakes.html
>
> What follows comes from my friend (Dr of Marine Biology) David
> Wachenfeld of the Great Barrier Reef Marine Park Authority:
>
> There are about seventy species of snake that inhabit the sea and/or
> estuaries. To
> the best of my knowledge, about seven of these are known to have caused
human
> fatalities. Just one of these species is single handedly responsible for
> about 90% of recorded human fatalities from sea snake bite. However,
> this species inhabits
> muddy estuaries and so does not commonly come into contact with people
> in Australia. Interestingly, Australia's foremost sea snake researcher
> contends that there have been no substantiated human fatalities from sea
> snake bite in Australian waters. It is worth noting that, in the species
> that have been studied, in around 70% of bites made in self defense, the
> sea snake with-holds the venom and the bite is merely a physical trauma,
> not a toxic one.
>
> The factors that determine how dangerous a snake is are mostly- fang
> length, aggressiveness, dose of venom delivered and toxicity of venom.
> All four factors vary alot between different species of sea snake. There
> are three species of sea
> snake that feed on fish eggs. These have small fangs and venom of low
> toxicity and can probably be considered as unable to kill a person.
> Pretty much all other
> species should be considered potentially lethal to humans. For divers,
> it's worth noting that most sea snakes have fangs less than 4mm in
> length and therefore are unlikely to be able to penetrate a wet suit of
> reasonable thickness. Olive sea snakes (fangs up to 4.7mm) and Stokes
> sea snakes (fangs up to 6.7mm) can both penetrate wet suits but I'm not
> aware of human fatalities from either species. Also, the species that
> inhabit coral reefs, where most people do most diving are generally not
> aggressive to people (assuming the people don't deliberately harass the
snakes!).
>
> Snakes are able to dislocate their lower jaw. But, exactly as you say,
> they do this
> to enable them to swallow large prey. Some sea snakes can swallow prey
> twice their own girth. But the dislocation ability of the lower jaw is
> only used to increase
> swallowing capacity not biting capacity. Snakes also have kinetic
> skulls. This means that the bones of the skull are not fused but can
> move relative to each other. This means that, when a snake has prey in
> its mouth, it can hold onto the prey with the teeth on one side, flex
> the skull and move the teeth on the other side forward on the prey. In
> this way, the snake can 'walk' the prey further into its mouth without
> ever actually letting go. Generally speaking of the 'ear-lobe or finger'.
> END QUOTE
>
> As to that last I suggested to him that I had thought that small
> extremities, such as the ear lobe and finger, were more vulnerable to a
> bite than anything larger and that I did not believe that snakes
> generally dislocated their jaws prior to an attack.
>
> As an amusing aside, he also said (partly in defence of a somewhat late
reply):
>
> > I was lecturing in reef ecology on a ship called the World Discoverer.
You may have seen it on the news as it hit a reef in the Solomons and nearly
sank about five
> days after I disembarked. Bloody good timing on my part.
>
> Cheers,
>
> Christian