Will the net and drumline removals result in a rise in shark attacks?

02 May 2009

The impact of the nets. There are less than 500 of this species in Australia - another country with nets.

The impact of the nets. There are less than 500 of this species in Australia - another country with nets.

Nets work by reducing localized shark populations, and during their 60 years of installation in Natal, have had a significant impact on those populations, as per studies conducting by Sharks Board themselves.

The population of sharks – particularly those targeted by nets – are drastically reduced in the Eastern Cape to their numbers prior to the nets installation, thanks in part to the meshing program. If the nets were removed, due to the slow reproductive and maturity rates of sharks, it would take decades for shark populations to recover. Given all the other threats to sharks including habitat destruction and overfishing, it is questionable if the local populations will ever recover. The nets have spent years doing their damage. Removing them at this point would not have an immediate impact.

While data was not effectively collected until 1978, anecdotal data available suggests records of very large numbers of sharks caught when meshing was begun. While annual total shark catches can fluctuate sharply, there is no question that today shark populations are very much smaller than in the 1950‘s & 60’s when attack rates were higher. In Durban, the total catch in the nets was 552 sharks the first year the seven nets were installed. By the second year it had plummeted to 182.

And, many people do not realize that one of the primary reasons nets were installed was due to the whaling that occurred off the coast of Durban. Shark populations were abnormally high due to the remains from the whaling stations that operated off the coast until 1975, providing sharks with a constant source of food. Whale oil and meat, which is a strong attractant to sharks, flowed from Durban beaches to the north or Amanzimtoti to the south - the exact sites of the most shark attacks during the peak of the whaling industry. With this source of food no longer available, it is unlikely shark populations will ever attain the sizes of those off Durban in the 50’s & 60’s.

The end of whaling in 1975 should have signified the reduction and removal of the nets, as shark numbers would have normalized, and there were no longer attractants luring sharks into situations that easily result in attacks. However, 1975 also saw the release of “Jaws”, and the sharks’ fate was sealed for another 30 years.

Comments (2) Leave a comment
  1. JaneRadriges June 13th, 2009 at 18:19 | #1

    I really like your post. Does it copyright protected?

  2. James Lewis May 26th, 2009 at 07:35 | #2

    As a regular visitor to the KZN lower south coast and an avid swimmer.
    I spend many hours in the water on the coast line and have never been threatened by a shark. I also scuba dive this coastline and have noticed first hand the decline in shark sightings.
    From my perspective, i totally agree with the removal of ALL nets and drumlines. What a false sense of security and what a barbaric practice.
    Is it not time we tool responsibility for our environment and acted with wisdom and compassion. Removing the apex predator in the ocean will have a knock on effect we cannot even begin to imagine.
    With education and understanding we can change the way we co-habitate and share our oceans.
    If you ever in doubt, make it your mission to see these beautiful animals up close. Over 400 million years with little change in design, how perfect they are for their environment.
    I look forward to my next encounter under water. A blessing and experience like no other.
    Thank you Seashepherd for your dedicated and focused involvement in this cause.
    For our oceans
    James Lewis

Allowed tags: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>
Trackbacks are closed.