Sunday, June 10, 2018

The Impact of GWS Cage Diving - Paper!


Bingo, and I cite,
"Best practice" among cage diving operations apparently consists in just teasing, but never actually handing any bait to the Sharks.
Were I a Shark hugger, I would immediately object that letting the Sharks waste precious energy on fruitless "hunts" is to be rejected as it is likely harmful to the animals.
Yup that would be yours truly a whopping ten years ago!
And now Charlie has concluded his investigation and comes to the following conclusion (emphasis is mine)
Although sharks are enticed to the cage-diving vessels with baits, industry regulations do not allow operators to feed white sharks and strict limits on the amount of bait and berley are now in place in South Australia and at other white shark cage-diving locations (Bruce, 2015).
Energy burden from the increased activity is, therefore, not rewarded by regular bait provisioning.

Some baits can, however, be consumed when sharks approach the baits using high speed or stealth (Huveneers et al., 2015).
The baits used in SA are composed of gills and stomach lining of southern bluefin tuna and are not as energy-rich as white shark’s natural prey while at these sites (e.g. pinnipeds). Whether the infrequent consumption of these baits provide sufficient energy to compensate for the increased energy expenditure associated with sharks interacting with the operators would depend on the calorific value of these baits and the frequency of white sharks successfully feeding on the baits, both of which are currently unknown (Brunnschweiler et al., 2017).
Spending time interacting with cage-diving operators might also distract sharks from normal behaviours such as foraging on natural, energy-rich prey like pinnipeds.
Combined, these suggest that the increased energy expenditure associated with cage-diving interactions might not be compensated for by either bait or natural prey consumption.

One could, therefore, argue that white sharks should be able to feed on some bait to compensate for the energetic losses resulting from interacting with cage-diving operators.
Bioenergetic models (e.g. Barnett et al., 2016) would, however, be necessary to accurately assess the likely effect of cage-diving on white shark energy balance and whether such compensation is necessary or beneficial. Beyond the potential for short-term energy intake, other aspects of food provisioning (e.g. quality of food, potential for changes in foraging behaviour) would also need to be considered.
Good one - and obviously, totally not surprised!
This is now the second paper (re-read this!) stating that NOT feeding is probably not a good idea - and whereas I concur that further investigation into the precise energy balance, etc may be beneficial, we should really not caught up in minutiae and finally do the right thing.

So what's it gonna be?  
Now that the evidence is in, will the regulators in Australia and elsewhere do the right thing and allow for proper feeding of those Sharks - or are they going to continue cow-towing to those in the populace who will contend that it would lead to more Shark attacks, and the like?
Remember that when it comes to feeding and conditioning Sharks, 99.999% is being perpetrated by the fishermen and not us - so assuming that it really is a big problem (spoiler = it aint: these are the real problems, with overfishing being the principal threat to Shark populations) let's maybe first look there! !
Anybody taking bets?

Anyway, enjoy Charlie's paper!
To be continued no doubt!

Friday, June 08, 2018

Guadalupe - more Shenanigans?

Indeed, a picture is worth a thousand words - click for detail! Source.

Watch.



Sigh.
Forget all that idiotic clap trap -  and no, no amount of soul searching and overcoming of personal phobias, or whatever, can detract from the simple fact that this is reckless and 100% illegal pure and simple.

And this shit?
That would be this dude, clearly a repeat offender along with his illustrious shark team, all of which are already planning their next trip for this fall, undoubtedly for the Sharks.
And the research permit for this? Questions questions!

And how about this last glorious feat.



Yes, that cretin is really brandishing a piece of Shark bait!
I mean - seriously!

Just great aint it.
And yet and despite of all the unequivocal evidence, CONANP appears once again either incapable and/or unwilling and/or too cowardly and/or, gasp, too corrupt to enforce its own rules and keep those people, and their serial enabler off the island!

Anyway.
To be continued no doubt!
 

Saturday, June 02, 2018

SOFA - quod erat demonstrandum!

The SOFA: a humongous area in the NE Pacific where GWS disperse to forage.

Behold - and yes it is long!



Synopsis here - and yes this is impressive as hell.
And here's a nice, and short video about the technology - again, very impressive in terms of scope but also cost!



And now, re-read this.
See what I mean?
  • The GWS are by no means "aggregating" but instead, they are actually dispersing in a huge area after having aggregated at the coast! I mean, seriously: watch the first video at 42.12: does that look like congregating to you?

  • In the SOFA (which is the much better name than CafĂ©) they very much appear to be foraging and not mating: case in point, just listen to what Barb's got to say at 1:21ff of the first video where she explains how the data illustrate that those Sharks engaging in ROD are most likely targeting prey like Bigeye Tuna.

  • Which obviously means that the GWS are mating in the known coastal aggregation spots like Domeier had postulated all along!

  • And those infamous, and totally cockamamie hypotheses by Jorgensen and Chapple, respectively, that they may be lekking or, gasp, sniffing for female pheromones?
    Right...

  • And oh yes that would very much be a q.e.d - just saying!
    And no this time I'm gonna be magnanimous and refrain from mentioning sniffing glue and the like! :)
But I'm digressing as usual.
Keep watching this website and also, keep watching this space.

To be continued no doubt!

Friday, June 01, 2018

Thanks for all the Fish!



I must say, this is really nice.
Firstly, because it doesn't do the usual touchy-feely treehugging thing but is instead very personal albeit a tad overly dramatic - the more as Juliette has been diving with us before and was by no means frozen in fear but did instead thoroughly enjoy the experience; and secondly, because this is the very first article about us that mentions the all-important toilet etiquette - and yes please do not pee in our rental wetsuits!

So, a big vinaka vakalevu from all of us.
Enjoy!