During the last ice age , the land bridge connecting Tasmania with the mainland allowed Tiger Snakes to move south . When the oceans rose , the Furneaux Group of islands was formed and the Tiger Snakes on these small islands became isolated . Chappell Island comprises only 323 hectares , and as previously mentioned is almost bereft of permanent water . These constraints were probably responsible for the early extinction of frogs and mammals , leaving only reptiles to survive . It is not clear when the muttonbirds colonised the island but it was a blessing for the snakes . Each year the birds return to the rookeries to raise their chicks and that means a banquet for the Tiger Snakes .
Incidentally , with my limited exposure to the wonderful islands in the Furneaux group , I always wondered what would be the minimum required size of an island to support a viable population of Tiger Snakes . Of course area is not the sole limiting factor , as the abundance and type of food resource , presence or absence of freshwater and predation all play an important role . Chappell Island seems pretty small to accommodate the estimated 1,414 ( Schwaner and Sarre , 1985 ) Tiger Snakes that are in residence , but there are even smaller islands in the group inhabited by Tiger snakes . In decreasing size , with area measured in hectares , these are : Preservation Island 207.45 ; Forsyth Island 166.85 ; Little Green Island 86.62 ; Little Dog Island 83.01 ; Chalky Island 41.31 ; Cat Island 38.82 ; and Storehouse Island 19.8 . Chappell Island Tiger Snakes are the largest of all the races , having only a single , saturating food source for the adults . Thanks go to Simon Fearn , Collection Officer with the Queen Victoria Museum and Art Gallery in Launceston , for providing me with this information .
This may be a Mecca for snake enthusiasts , but from an ecological point of view not everything is rosy . Since the removal of the sheep , Boxthorn ( Lycium ferocissimum ) has spread in some parts of the island and is creating a huge workload for the rangers involved in the eradication of this incredibly resilient , thorny bush , which is very hard to control and destroy . When cut off at the base , the roots must be poisoned and the branches burned , otherwise both will sprout again . Although progress was clearly visible compared to last year , further funding and other resources from the government would help to speed up the process . More hands on the ground and more machinery such as additional front-end loaders and weed mulchers would make a huge difference . The weed mulchers are on rubber tracks so they do not leave a large footprint on the fragile rookeries and grasslands .
Chappell Island is of great importance to the Aboriginal people , as for millennia ( dating back at least 20,000 years ) it formed an important part of their seasonal foodgathering cycles . It is therefore vitally important to preserve the ecological integrity of the island for future generations . The TAC and their employees take pride in the island ’ s long and rich Aboriginal history , and strive to maintain its historical and cultural significance , as well as improving and facilitating access for the Aboriginal community . The rangers act as tour guides during community visits ; they showcase their work and point out the sites of the old muttonbird sheds and places of relevance to Aboriginal heritage .
This is a very special place for me too ; as a teenager I read Eric Worrell ’ s book Song of the Snake and I knew then that one day I too would step foot on the island . I am grateful to the Aboriginal people of Tasmania for allowing me to visit their island for the fifth time and I wish them every success with future management and maintenance . Look after the plantina ( the word for snake in palawa kani language ).
Top left : a landscape pockmarked by muttonbird burrows . Above ( slide show ): Justin Kneebone holds two Tiger Snakes ; a compulsory photo on each trip to the island . Some of the rangers needed a little encouragement to participate in the ‘ hands on ’ experience .
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