Proof is in for sharks and hooks

I HAVE been amused by the rejoicing from the ECOfishers at the announcement of the revocation of the new protections at Fish Rock and Green Island to stop accidental hooking of the critically endangered grey nurse shark.

The revocation was announced by the new Minister for Fisheries, Katrina Hodgkinson.

However, the wild rejoicing might have hit a snag.

Fish Rock is considered the key aggregation site for this shark on the east coast and has been shown to have recorded the most number of sharks with hooks embedded, which can lead to a slow and painful death through starvation or infection.

The three month lifting of the ban is, according to the Coalition, so that an independent review can be done of the independent science already amassed.

That would not be a problem except under the precautionary principle of the Environmental Protection and Biodiversity Conservation Act it would be proper scientific procedure to carry out the review and only then remove any unnecessary protection.

By removing the protections first it appears to the general public that Katrina Hodgkinson has already decided the result will be that no restrictions against fishing with bait, live bait and jigs are needed to protect the shark.

Either that or she is ignorant of proper scientific method and completely without care for threatened species.

So the review of the independent science goes on, but the opponents of shark protection at Fish Rock may not be delighted to learn that the definitive proof that grey nurse sharks do actually take baits and are interacting with jigs at Fish Rock is in.

A scientific paper titled ‘Investigating the Behavioural Response of Grey Nurse Sharks to Recreational Lures and Baited Lines’, by Dr Will Robbins and Dr Vic Peddemors of Cronulla Fisheries Research Centre of Excellence, has just been released and placed on the website of the NSW Fisheries Department.

According to the scientists involved, “gear types used in this research were commonly used by recreational fishers at the study site.

“Hooks were disabled on all gear types, with fish and shark interactions monitored using underwater video cameras which fed a signal directly back to the boat.

“Previous studies have found these cameras have no effects on the behaviour of sharks.”

Sampling was conducted through three different experiments looking at bottom-set baits, trolled lures and jigs. Experiments consisted of 800 bait trials of four different baits, 625 lure tows (537 km) of 16 different lures and 861 jig drops of eight jig types.

Robbins and Peddemors concluded that grey nurse sharks clearly interact with stationary baits fished close to the sharks.

All types of bait were taken at all times of day, and grey nurse sharks were the only bait-takers after dusk.

Even the least taken bait types resulted in frequent (10 per cent) shark interactions, demonstrating that bottom- set baits pose a high interaction risk when deployed around grey nurse shark aggregations.

None of the trolled lures and bait elicited any reaction from grey nurse sharks.

Although there may be indirect effects of sharks targeting fish that have been caught by lures, the lack of any interactions with trolled lures, and the low number of sharks recorded carrying lures suggests that trolling represents minimal direct risk to grey nurse sharks.

Knife jigs and soft plastic jigs pose risks to grey nurse sharks while fished close to the bottom.

Most interactions occur through jigs hitting the shark, resulting in foul hooking.

This can occur relatively frequently when fishing in close proximity to grey nurse shark aggregations.

Plastics and jigs designed for deeper water fishing had higher interaction rates than vertical jigs as they are deployed close to the bottom for longer periods of time.

So there you go. The fishers have the absolute scientific proof they were asking for. Grey nurse sharks have been proven to take baits.

Who would have thought a top marine predator would eat fish offered to them on a line? Who would have thought dropping a knife jig down amongst them and reefing it skywards might impale a shark?

Most fishers do not target sharks but, unless they are using magic hooks, it looks like they would likely hook one more than 10 per cent of the times they put a slab or live fish in front of them, and this proven scientific fact begs a couple of questions.

Knowing this will the Minister Katrina Hodgkinson continue to allow an endangered animal to be cruelly injured despite her own department telling her it is happening while the “consultation” with the public goes on, or will she listen to the science this time?

And how desperate is the Coalition to win the Shooters and Fishers vote in the Upper House?