iHerp_Australia_-_May_-_June_2018

the shed that would serve as the venue for the workshop.
So that job was done. After the other guys had arrived by
boat, Justin and Chris decided to hold the theoretical part
of the workshop inside the shed, as it was quite hot and
sunny outside; not ideal conditions for handling snakes.
Ambrose and Grahame were familiar with Tiger Snakes
and very enthusiastic to participate, but some of the other
rangers needed a bit of encouragement to put their hands
on the snakes. Chris and Justin dispelled some of the
fallacies about snakes and pointed out facts such as
snake’s eyes look cloudy before sloughing - it’s not that
they’re going blind. As most of the Tiger Snakes had
ticks, the rangers were shown how to safely remove
these parasites, as well as how to get the snakes in and
out of hoop bags and how to use a hook and pinner
effectively.

Then heavy clouds suddenly appeared in the sky and it

was perfect timing to put the theory into practice outside.

It didn’t rain, so some of us set out to look for more

snakes. As always, herping on Chappell Island is a

bonanza! I remember in 1984 and 1986 a lot of the adult

Tiger Snakes were dark brown and banded, however, in

my last two visits I have only seen black specimens

without markings. Chris desperately wanted to see a

juvenile (they are quite rare) and he finally found one; a

nicely banded specimen about 80cm in length. Unlike

the adults this youngster had plenty of attitude.

Why are so few juveniles seen? They are having a hard

time on the island and I would hate to guess what the

survival rate is. Although there are mice and skinks

present, generally speaking the food resources for small

Main: the dark colour of Chappell Island Tiger Snakes helps

them to soak up the sun on cold mornings.

Insert (above): White’s Skink (Egernia whiteii) is common on

the island and represents an important foor resource for juvenile

Tiger Snakes.

Insert (right): the workshop included training on catching,

handling and first aid.

snakes are meagre and the summer is short. Judging by

the number of adults with stumpy tails, I suspect the

gulls are attacking them, and of course if they happen to

pick up a snake that is small enough, it goes straight

down the gob. In the past there were also feral cats on

the island, which contributed to predation on young

snakes, but according to the rangers, after a successful

trapping program there is only one left. In addition, Tiger

Snakes are known to be cannibalistic, so the juveniles

avoid the muttonbird rookeries where most of the adults

reside, and instead mainly inhabit areas of grassy tussock

and large shrubs, which serve as refuge when danger

approaches. So, whilst the adult Tiger Snakes have no

predators, the young ones are constantly under the pump.

Many of the adult snakes have scarred necks from ticks,

which doesn’t add to their good looks, but they don’t

seem to be infested to the point where they can not

function. Apart from a small spring on the southern side,

there is no permanent water on the island, so the snakes

don’t have the opportunity to soak themselves to get rid

of the ticks. No water means there are no frogs, and

hence likewise there are no copperheads on Chappell

Island. The Tiger Snakes feed largely on muttonbird

chicks during the breeding season, but once the chicks

are too big it’s the end of the feast. Rats and mice

provide little supplement to the snake’s menu; it’s the

fatty, oily and smelly chicks that constitute the main

course. The window of opportunity only lasts about six

weeks in the summer months before the chicks are too

big for the snakes to swallow.

‘Chappell Island is

literally moving with big Tiger Snakes.’