Recently the Department of Primary Industries (fisheries) released its annual report on the operation of its beach netting program for sharks, which runs from Newcastle to Wollongong.
The department has to report publicly since the culling program for sharks was formally listed in 2003 as a process that threatens animals listed as endangered/threatened. These include species of turtles, mammals (such as whales) and some sharks, like the grey nurse.
The culling is undertaken via gillnets set on 51 beaches over the swimming season. The nets do not provide a barrier to sharks visiting the beach, but are designed to reduce shark populations to levels that some scientists believe do not pose a hazard to swimmers. Over many decades, the program has significantly reduced shark numbers in the Newcastle to Wollongong region.
As has been the case for many years, the most recent report documents that the numbers of potentially hazardous sharks (bull, white, tiger) caught is very small – being 12, 28 and 11 respectively. Of these 3, 6 and 3 were recorded from the Illawarra (Wattamolla, Garie, Coledale, Austinmer, Thirroul, North and South Wollongong).
The nets take a far wider number and variety of non-target species, including sharks not deemed hazardous (such as smooth hammerheads and grey nurses) plus turtles, species of rays and the very occasional marine mammal. For the Illawarra, the most common species in this category is the Southern Eagle Ray. Not all of the animals caught die. Some, including sharks, are released alive.
Compared to the number of sharks ‘out there’ the number taken in this program is very small. The estimated population size of adult great white sharks in eastern Australia is 750 with a total estimated population of about 5500 (i.e. including juveniles). Bull and tiger shark numbers are unknown. We know these animals move up and down the coast (a lot) and we know from the listening stations (such as the one at Stanwell Park) that they visit our beaches (or, at least, 500m off them) relatively frequently. We know shark ‘attacks’ are far less frequent than drownings. The culling program does collect information but whether that helps bather safety or is just of scientific interest is always debated.
There is no easy answer to the sharks on beaches question. Some worry about being bitten, some don’t. Removing sharks has ecological consequences that some people think are unacceptable, but others are OK with.
