Entries in aquarium (11)
Here’s episode two (of four) of my conversation with WREK scientist/DJs Pete Ludovice and Bill Hung. In this bit we’re talking about whale shark research in Mexico and the idea of conservation by payment for ecosystem services. Check out the rest of their archive here, and listen live on Wednesdays at 12 (details in the link)
Two weeks back I did an hour long radio interview with WREK 91.1, a public radio station out of Georgia Tech, for their science show Inside the Black Box, which is described by its hosts Pete Ludovice and Bill Hung as “Science, only funnier”. Pete and Bill are both faculty members at Tech and also stand-up comedians.
I am going to post the interview here in four more manageable parts over the next week or so. Here’s Section 1, where we talk about how public aquariums came out of the naturalist movement of the Victorian era.
If you just can’t wait for the rest (and who could blame you, he says, sotto voce and without a hint of irony…), the whole interview with lead-ins and musical breaks is here.
While you’re at it, put a reminder on your calendar to listen to their live webcast each week on Wednesdays at 12. They have sponsorship from NSF and do great work; I appreciate their permission to post the interview here.
With a grateful hat tip to DSN’s DrCraigMc via Twitter, I give you (well, really the Telegraph gives you)- TA DA! - the world’s smallest aquarium. Click the link or the pic to see it in all its diminutive glory.
Just for scale, the Ocean Voyager exhibit at Georgia Aquarium would hold 2.4 billion of those bad boys. That means that aquariums effectively span 9 orders of magnitude in size. We’ve come a long way, Anton Dohrn…
If you’re into podcasts, my colleage and good bud from the University of Florida, Dr. Roy Yanong, is doing a series called Aquariumania. Check them out. Roy is a veterinarian and fish health researcher and his latest podcast is an interview with fish curator at SeaWorld, Jim Kinsler. He’s got other gems too, like this interview with Shedd Aquarium water quality expert Allen Lapointe and this one with Dr Helen Roberts, one of the few private veterinary practitioners for whom the bulk of their business is made up of fish patients.
Bear with some ads early on and you’ll be able to listen to some of the current luminaries in aquarium health, interviewed by one of their own. Kudos to Roy for embracing the new media! If you’re into aquariums and fish health at all, they’re well worth your time.
Back in Spring 2009 I attended a creative and unusual meeting at the Aquarium of the Pacific in Long Beach CA, which their director Jerry Schubel had organised to discuss pressing issues facing the worlds oceans. It was a fantastic mix of scientists, film-makers, journalists, bloggers, game designers and social scientists, and it really opened my eyes to the sucky job we scientists sometimes do in explaining the importance of our work. Everytime one of the scientists lapsed into jargon or science-ese, one of the others would jump up and say “ya lost me” and drag us back to reality. It was very enlightening, to the point where it actually inspired me in part to start this blog.
One of the final products of that meeting is now in print. The four key areas we identified and discussed were summarised in reports that are intended to be part of educational packages that grew out of the workshop. I co-authored the one about oceans and their connection to human health. You can get it, and the other three on Coastal Hazards, Fisheries, and Pollution, here.
Whale sharks are the largest fish in the oceans; they can grow to 20m in length and weigh many tons, although 7-9m is closer to the common average these days. Despite their tremendous size, scientists don't know that much about them. We know that they eat plankton and that they live in the tropical oceans throughout the world and there have been quite a few papers reporting their presence in different waters, but these represent only the most basic foray into the biology of a species. More recently, there's been a few more including one that explores genetics (Castro et al., see below) and some that have started to explore behaviour (see Brunnschweiler et al.). Up to this point, the focus has all been external; that is, only the biology that can be observed from the outside. That's no surprise really; its a logical place to start and there are some huge logistic challenges to working with whale sharks, as you can probably imagine.
There are 4 whale sharks in the collection at Georgia Aquarium in Atlanta and I have been lucky enough to work with these amazing animals since 2006. Part of that work has involved veterinary examinations, which has allowed us, for the first time, to look at aspects of the internal biology of whale sharks. The first part of that work is now in print: a paper I co-authored with the aquarium's principal clinical vet, Dr. Tonya Clauss, and a colleague from National Aquarium in Baltimore, Jill Arnold (Jill is an expert in medical techniques, especially blood work), which is in the latest issue of Aquatic Biology. Our paper is a discovery-based one (i.e. not testing a specific hypothesis) about the nature of the blood of whale sharks, both the cells and the chemistry of the blood serum. Its open access, so you can get it at the journal web page here
In it, we show that whale sharks have blood that is fundamentally similar to that of some other sharks, specifically the bottom dwelling ones like nurse sharks and wobbegongs, but pretty different from the toothy predatory sharks like great whites. They have very large red cells, actually white cells too, but this is something they share with the bottom dwellers, so it appears to be a feature of the group rather than a function of the size of the whale shark as such. Whale sharks are the only pelagic members of that group, the order Orectolobiformes. Why such large cells, then? Our study didn't answer that question, but my best guess is that they have relatively low metabolism compared to the carcharhinids, which may need the high relative surface area of smaller red cells to improve the movement of oxygen in and out of cells. This is the first of several hypotheses that we can only begin to pose because of these first discovery-based efforts.
I can't tell you how excited I am that we can begin to share what we've been learning at the Aquarium. The chance to work with whale sharks is a real gift for a fish nerd like me, and the opportunity afforded by having access to them in the more controlled environment of an aquarium makes it possible to do safely and effectively research that has been prohibitively difficult with free-ranging whale sharks up to this point. Of course, the ultimate goal is to extend that work to compliment the field research, and I look forward to telling you more about that in future posts.
Brunnschweiler, J., Baensch, H., Pierce, S., & Sims, D. (2009). Deep-diving behaviour of a whale shark during long-distance movement in the western Indian Ocean. Journal of Fish Biology, 74 (3), 706-714 DOI: 10.1111/j.1095-8649.2008.02155.x
Castro, A., et al. (2007). Population genetic structure of Earth's largest fish, the whale shark ( )
Molecular Ecology, 16 (24), 5183-5192 DOI: 10.1111/j.1365-294X.2007.03597.x
Dove, A., Arnold, J., & Clauss, T. (2010). Blood cells and serum chemistry in the world’s largest fish: the whale shark Rhincodon typus Aquatic Biology, 9 (2), 177-183 DOI: 10.3354/ab00252
Manta rays (Manta birostris) surely vie for the title most spectacular among the large animals in the ocean. Not only do they grow to enormous sizes, but they are placid, graceful, and generally unafraid of humans, which means we can get close to them in the water and really appreciate how incredible they are, up nice and personal. I always thought that mantas were a one-of-a-kind species - the only member of its genus - like humans, whale sharks, koala bears or killer whales. Luckily, Andrea Marshall is not like me. She and her colleagues took a closer look at the body features, colours and patterns on lots of mantas from all around the world and they concluded that there are at least two, and possibly even three, manta ray species. They’re not the first people to propose this, so technically what they have done is “resurrect” the name Manta alfredi, the Prince Alfred manta, which had been made a synonym of Manta birostris some time ago (read the paper for the full sordid taxonomic history of mantas). The differences between the two species are subtle and mostly to do with the colour of the lips, wings and shoulders, the spots on the belly and the presence or absence of a bony mass near the base of the tail, but nonetheless they probably reflect real differences between the animals and, under the current definition of “species”, they probably cannot successfully interbreed. The third potential species they call “Manta sp. cf. birostris” which is taxonomist shorthand for “as-yet undescribed manta species sort-of like M. birostris”.Georgia Aquarium, you may have seen one or both of their mantas in the Ocean Voyager exhibit. If you look closely at these and compare them to the Marshall paper, you’ll see that one (called “Nandi”) is Manta alfredi and the other (“Tallulah”) is more like Manta sp. cf. birostris. Its slightly ironic that in light of this new paper, neither of them is the “actual” or original “manta ray”. Of course, they are both still spectacular animals!
Who cares about all this anyway? What does it matter if there’s one or three or a dozen manta species? As it happens, it matters a great deal! Taxonomy underlies everything else in biology. What good is a population estimate, for example, if that estimate confuses two species? We would grossly overestimate both, potentially leading to overexploitation. More generally, how can we understand migration patterns, breeding grounds, diets, ecological roles or behaviour, if we are constantly confounded? These are, of course, somewhat self-centered concerns about the quality of our science or management decisions; a species count is about the most fundamental measure of nature that we have, and those sorts of diversity stats are predicated on a decent taxonomy. Consider this: how much of a ginormous “oops!” would it be if we were to protect a species in one area of ocean, only to learn that the animal in the area we didn’t protect was actually a different species? Perhaps a more important reason it matters is for the mantas themselves and the rest of their ecosystem. Each species has an intrinsic right to exist and a value to the ecosystem its part of.
I just love the idea that even for familiar, charismatic mega-animals like mantas, if we look a little closer, nature shows us hidden diversity: surprising, unexpected, and exciting.
Marhsall, Andrea D., Compagno, Leonard J.V., & Bennett, Michael B. (2009). Redescription of the genus Manta with resurrection of Manta alfredi (Krefft, 1868) (Chondrichthyes; Myliobatoidei; Mobulidae) Zootaxa, 2301, 1-28
All this makes the invasion of the Atlantic seaboard by the Pacific lionfish, Pterois volitans, all the more remarkable. Lionfish are flat-out spectacular! Long prized as an aquarium specimen, they have bold stripes that spill over onto their fantastically long and showy fins; their scientific name even means "fluttering wings". The sheer beauty of lionfish doubtless plays a role in how they came to invade the Atlantic in the first place; most likely they were an escaped or released aquarium species that found itself able to survive quite nicely in the conditions of the coastal Atlantic. The beauty of lionfish conceals a dangerous secret - venomous spines on their dorsal (back) and pelvic (bottom) fins. While they won't kill a person; they cause excruciating pain. I've never been stung by one, but I have been stung by related scorpionfish (most recently the short-spined wasp fish) and the feeling is not one I'd care to go through again!Yucatan peninsula. Typically considered to be a rocky or coral reef species, they've now been found swimming in the intracoastal waterway; that labyrinth of salt-marshes, channels and estuaries, engineered to allow safe passage of boats along the US coast in wartime. This is sort of an unusual location, but it speaks to the adaptability of this remarkable fish.
So, what to do about such an animal?? Well, that's a tough one. Invasive species (or more accurately, moving species around) are one of the greatest impacts humanity has had on natural environments, and there are very few cases where we have successfully eradicated or controlled an invasive (but see prickly pear in Australia), more often they just become part of the furniture and we get used to their impacts on the local ecosystem. Introducing natural enemies (diseases, predators) like they did for prickly pear is a dangerous game; if you tried to get the Cactoblastus moth introduced to Australia in these days of stricter biosecurity, you'd almost certainly be denied. You can easily get into a "spider to catch the fly" situation too; in fact that's how cane toads were introduced to many places - to control sugar cane beetles (which they suck at). Perhaps the best approach is to do what we do best - create a market that will promote human efforts to exploit them, and then rely on the Tragedy of the Commons to do the work for you. This has already been proposed with Asian carp. Fortunately, it turns out that lionfish are not only spectacular aquarium fish, but also delicious in a white wine sauce. I am sure that if we set our minds to it, we could do as good a job wiping out this species as we have with so many others. So c'mon everyone and grab a fork; Save a reef - eat a lionfish, today!
(Photo and graphic from NOAA)
Congrats to the folks at Shedd Aquarium on the birth of a baby beluga whale - one of my personal favourite species (you will never meet a sweeter disposition in all the oceans). Tell me this isnt the cutest little grey slug on the planet.
The little fella was born head first, which makes great sense for humans - where taking that first breath of fresh air is just a birth canal away - but not so great for whales, where you have to hold your breath until the rest of you comes out, before rushing to the surface. In whales, such a head-first birth is considered a breech birth. Nonetheless, he's apparently doing just fine.
He'll be grey for the first couple of years of life and then gradually get ever whiter, until he earns the common name for the species: "beluga" is Russian for white (and is actually pronounced more like b'loo-HA, with the H way in the back of the throat)
When I thought a little more about it, it shouldn't be at all surprising that ICUN picked 70% aquatic species for their list; after all, 70% of the earth is covered in water...