Guadalupe Great Whites - Paper!

Location data for the four satellite-linked radio-telemetry-tagged female white sharks during the pupping phase.

Epic!

Read the paper!

No I'm not going to write a synopsis as it is open access, short, incredibly interesting and informative, and crystal clear insofar as it does not contain any obscure scientific lingo - and anybody ever wanting to talk about Great Whites needs to have read it!
Yes, female GWS follow a two-year breeding and migration cycle, something no PAT tag has ever been able to document!

And, there is this.

Jorgensen et al. have proposed an alternative life-history hypothesis that is contradictory to the hypothesis proposed by Domeier. The major difference between these hypotheses pertains to the timing and location of mating. Jorgensen et al. speculated that white sharks are mating during their offshore phase, whereas Domeier proposed that mating occurs during seasonal, near-shore, adult aggregations...

The offshore-mating hypothesis is based upon the conjecture that a described vertical-diving pattern (rapid oscillatory diving (ROD)) is a result of a lek-like mating behavior in the core of the SOFA. This interpretation is problematic from several perspectives. Lek-like mating systems involve the gathering of males at a traditional site for the purpose of ritualized courtship display. The males compete for the attention of females, and in turn, the females select a specific male for mating. Although the peak in ROD behavior, and thus presumed offshore mating, occurs during June/July in a period when the distribution of males temporarily constricts, even the constricted offshore space is vast (estimated to be about 64,000 km²). Lek-like mating would require the males to be in a very small space to allow females to observe the courtship of several males at once. No electronic-tag data have ever indicated that sharks are densely populating a small, traditional offshore site. Lek-like mating systems have been described for some species of fish, but leks have never been seen among elasmobranchs. Females that mate in lek systems select a single male deemed superior to other males, thus the fact that white-shark pups from a single litter tested positive for multiple paternity argues against lek-like mating for this species. 

It is challenging to ascribe any behavior to vertical movement data in the absence of visual observations. The seasonal constriction of the SOFA and the ROD-type diving pattern could be due to the pursuit of a seasonally available prey. An expedition to this region during the constriction identified the presence of three species of spawning squid and sperm whales, but again, the absence of behavioral observations deems it impractical to assign any cause to the ROD diving pattern. Diving patterns and mating systems aside, there are other strong arguments against the hypothesis that white sharks are mating during the offshore phase of their migratory pattern. First, electronic-tag data indicate that males and females are largely segregated during the offshore period, and second, the proposed mating during June/July would equate to December/January pupping (accepting the 18-month gestation estimate). Females arrive at adult aggregation sites approximately in September, and depart in December to end of February. No YOY have been seen at the adult aggregation sites, no obviously pregnant females have been sighted at GI, and pupping is known to occur approximately April through July.

Bingo!

I really had to laugh out loud - remember?

Basically exactly what i said - which begs the question, does the man read my posts? What I did not know was the fact about multiple paternity - the exact opposite of what would be expected in lek mating!

Eat that, Sal!

Anyway.

Bravo Michael Domeier and Nicole Nasby-Lucas - this is truly seminal stuff. And, thank you for the chapter about conservation concerns! 

And I repeat: read it!

And now, watch this.

Right.

Looks like the bunch of dipshits with an opinion and a keyboard has spawned a dipshit with an opinion and a camera who is now publicly spouting the usual moronic rubbish all the way to having the audacity to post that picture of Junior! 

All so pathetically SvS.

But fear not, I'm not gonna dwell on the latter. 

As per Patric's update and after now many weeks of him having produced zero, zilch, nana da nada evidence for his assertions, I'm done with the man and his verbose excretions!

Anyway.

Does that mean that I now endorse SPOT tags?

It depends!

Research does not consist in slapping on some tags in order to then look at what happens - the scientific method demands that one formulate a (plausible - see the lekking fiasco!) hypothesis and then test it, for which one needs to employ the adequate tools.

So IF the hypothesis requires gathering multi-year data about a species that conducts large migrations and IF the animal comes to the surface frequently which is necessary for up-linking to the satellite, and IF the questions being asked are important, then I absolutely support deploying SPOT tags!

As I said here, research about philopatry is vitally important for conservation purposes!

Example?

The GWS that aggregate and regale the cage divers at the Neptunes are likely to be among the very same animals that munch on unsuspecting aquatic recreationists in Western Australia, quite possibly in tandem with GWS that travel there from SA.

Both hypotheses have already been validated by PAT tagging tracks, and possibly even via acoustic tagging - but we still don't have the full picture insofar as we don't know where they mate, where they pup (or do we?) and why, exactly, they and some of the SA GWS travel to WA.

That is simply vital information if we ever want to understand and then address and manage the mess in WA and protect those Sharks - and of course the people!

And how would one go about in gathering that info?

Assuming (which is not a given!) that the females of that Australian population follow the same 2-year cycle as those from Guadalupe, then SPOT tags would be the ideal tool, vastly superior to PAT tags that do not have that longevity! The ideal tagging location would be the Neptunes where the Sharks aggregate, and the operators there should really consider inviting a knowledgeable GWS researcher - out of intellectual curiosity but also very much in order to safeguard their assets!

But not Fischer's wandering circus!

I dislike the man but that's obviously not the issue.

The issue is that by today's standards, his methods are unnecessarily invasive. Domeier has proven that very large GWS can be caught and then tagged whist submerged; and he has also developed a cradle for the tags whereby there is only one single attachment bolt, thus greatly reducing the risk of fin damage. 

Is that perfect?

Certainly not - but it's a great improvement and in view of the importance of finally gathering the necessary information about that population, I for one could personally live with some possibly warped or shredded fins. But I would not publish any tracks - at least not at this time of public pressure and according political brinkmanship in WA. Imagine the fiasco of showcasing the Sharks' real-time location, only to have one executed by some overly zealous government bureaucrat - highly unlikely but why take that risk!

But I'm digressing as always.

All I really wanted to say is, epic and congrats!

Read the paper!