Thursday, December 19, 2013

Lemon Shark Philopatry - Comments by Doc!

PIT tagging of juvenile Lemons, Bimini - source.


I just found this in my inbox.
This is what it takes to produce real and like I said, simply epic research - not this amateur shit, and I cite,
We conducted the tests of potential approach preference of sharks with regard to human body orientation in the Northern Abaco Islands, Bahamas, on 8 days between July 7 and 24, 2009. Later on, several days were excluded due to the chosen criteria.

But I'm digressing as usual.
Without further ado, here are the remarks = two cents :) by Doc - needless to say that I am honored!

Reply to Da Shark’s blog on the recent publication of our lemon shark genetic research in the journal Molecular Ecology as reported in the New York Times: 

Like the EverReady bunny, we are still going….and in June 2014 it will be year 19. 
There is still a lot more to be learned from our continuing and longitudinal study of lemon shark genetics but here's the way this all played out according to my foggy recollection. 

In 1990 the Bimini Biological Field Station was established. 
That year we became interested in shark genetics and actually did our first "PIT project" collecting genetic samples and PIT (RFID) tagging the little lemons. We caught 90 lemon sharks that June but alas that was the last I ever heard of the samples which were sent for analysis to a black hole the UK. In addition we caught no lemon sharks in November 1990 so I figured that was that. 

In 1995, I was contacted by a young graduate student, Kevin Feldheim working in Mary Ashley's lab at University of Illinois-Chicago. 
He wanted to study our little lemon sharks but had no funds. I thought we could support Kevin at the station if Mary could deal with his laboratory work. So I went to Chicago and we got into a discussion about NSF funding. I had been relatively successful with NSF in the past but after recovering from cancer in 1989 I hated the idea of writing one of those damned proposal "books" again only to get it turned down. However working together in Chicago the three of us wrote a first-class proposal and MIRACLE! The combination of Mary's expertise and my reputation as some sort of shark maverick did the trick and NSF granted us funds to bring Kev to Bimini for a few years to do the field research. So starting in 1995 and continuing even until today we tagged sharks and collected genetic material; and for three years, funded by our NSF grant we sampled over 700 young lemon sharks at Bimini. 

Of course shark genetics did not start with our project but these earlier studies were mainly set up to determine the relationship between species---molecular taxonomy. 
In contrast, we were interested in the genetics of breeding biology which was entirely unknown for sharks as well as most other aquatic vertebrates. 

I think there were three reasons for the fantastic (to me) success of this project: 
First was Kevin Feldheim who carried out hundreds of experiments until he found the key to DNA finger printing lemon sharks....microsatellite alleles with high variability conferred by high repeat numbers (this laid the background for the research of Joey DiBattista and Demian Chapman); second, the amazing lemon shark, an animal that repeatedly lent itself to manipulation as a model species (think white rat!) allowing us to study the biology of large sharks; and three, the islands of Bimini for which the vagaries of sea level rise and fall created a small lagoon that was the perfect breeding ground for lemon sharks. Importantly unlike Florida only 42 NM to the west, our Bimini lemon sharks hung around the islands for up to 8 years and could be captured time and time again. 

Once Kevin laid the groundwork to open up questions that were previously unanswerable, we undertook a concerted effort to mine this treasure of marine biology. 
Enter Dr. Ellen Pikitch and the Pew Foundation: Already the lead author Dr. Damian Chapman had been to the Sharklab years ago and so had Ellen but now things got serious. I was nearing retirement and thinking about the future funding of the Sharklab. Ellen got the idea to fund the station with a generous 5-year PEW grant and in exchange we would share all the data with her then doctoral student Damien Chapman. This was a dream come true for all of us. Now we had another grant that would see us through the lemon shark's estimated time-to-maturity...shown by my student Craig Brown way back in the 80s to be 12-14 years after birth. 

Simultaneously we began to develop techniques to search out and wrangle the potentially dangerous adult lemon sharks that come into the lagoon for mating and parturition every April and May. 
We were eventually able to predict when they would show up, how to capture them and even learned to do a kind of mid-midwifery to assist in the birth process. This technique provided DNA from both the Mom and all her pups. It then became a matter of continuing the collections until a dozen years went by in hopes that a youngster born in Bimini in 1995 or later survived to adulthood and could be identified in Kevin and Joey's lemon shark pedigree. 

Well....incredibly our gamble our came true. 
After about a dozen years a few survivors began to appear in the lagoon and we thought this was just amazing. Talk about tenacity and collaboration! We predicted based on two decades of prior study that the lemon shark would return---and we toughed out the years and effort to do the labor-intensive but hugely enjoyable task of collecting lemon shark pups for a dozen years and beyond, braving shark bites, tropical thunder storms, dangerous lightening, swarms of mosquitoes, no real sleep for weeks on end and a myriad of other political and biological barriers including serious damage to the nursery from a ridiculously huge resort development on tiny little Bimini. 

Together in collaboration between three research institutions, the Bimini Biological Field Station Foundation, University of Illinois-Chicago and Stonybrook University the study that Da Shark so eloquently referred to was accomplished. 
If you actually have time to read this missive you will see that the influence of one group or the other to the success of this remarkable research is progress could have been made without the three institution's cooperation. And even today, 19 years after the project began we are continuing the annual collection of genetic data from not one but three sites in hopes that one day the lemon shark and its vulnerable nursery habitats will receive the protection that they truly need. 

Just my two cents. doc 

Dr. Samuel H. Gruber (Emeritus) 
Division of Marine Biology and Fisheries 
Rosenstiel School of Marine and Atmospheric Sciences 
University of Miami 
Bimini Biological Field Station Foundation 
9300 SW 99 St 
Miami FL 

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