You are currently browsing the tag archive for the ‘captivity’ tag.

whiteabalone00.jpg

Of all of the world’s abalone species, the white abalone (Haliotis sorenseni) has the sweetest, whitest, most delectable meat…or so I am told: I have never eaten one.  Indeed, it is increasingly unlikely that anyone will eat one again.  A horrible thing happened to the white abalone in the seventies (and to lots of other people and things too, but we need to stay focused).   A commercial fishery came into existence and, although it lasted for less than a decade 30 years ago, it seems to have dealt a nearly fatal blow to the white abalone.

White abalone are herbivorous gastropods which are not exactly white—they have an orange foot with tan sensory tentacles (!).  They are herbivores which live on rocks surrounded by sand channels at about 25-30 meters of depth (80-100 feet).  They can be found in Southern California and the northern parts of the Baja peninsula.  White abalone are broadcast spawners.  They release…uh, their gametes into open water in large numbers.  The abalone fishery of the seventies and early eighties thinned their numbers so drastically that they do not exist in proximity to each other.  White abalone live a maximum of about forty years, so the last natural specimens are dying off without reproducing.  They are broadcasting their genetic information into the open ocean with no complimentary abalones nearby to produce offspring.

abalone-spawning.gif

The NOAA is working with various partners to save the abalone.  The administration and various mollusk lovers and malacologists have created a captive breeding program at the University of California-Davis Bodega Marine Lab.  Although they have successfully spawned enormous numbers of white abalones, the larval shellfish do not do well in captivity and the species’ ultimate survival remains an open question.  Fortunately, in pursuing the goal of saving the white abalone, the scientists have learned a great deal about abalone disease treatment and prevention and how to maintain water suitable for the young sea snails.   The whole sad episode seems to indicate several troubling things about our (in) bility to manage marine resources—and yet, through extraordinary countermeasures we have forestalled complete disaster.  I wonder if the white abalone will manage to come back based on all we have learned.

whiteabalone02.jpg

170723-snooty-manatee-died-se-137p_2726510bb7ef9af1df7694f38b8b7ea9.nbcnews-ux-2880-1000.jpg
Last week I blogged about the end of the desmostylians, a group of aquatic mammals driven into extinction by competition from the gentle (but implacably hungry) manatees. Since then, I have been worried that people are going to think I am anti-manatee. That is why I would like us all to take a moment to say farewell to Snooty the manatee, the world’s oldest captive manatee who died on Sunday (July 23, 2017) a day after his 69th birthday party. Since 1949 Snooty has been entertaining and educating visitors to the South Florida Museum in Bradenton, Florida. His death was not a result of old age, but was instead a tragic accident involving the failure of a protective hatch which closed off a maintenance-only section of the aquarium.
Apparently in the modern era, manatees in the wild usually live less than 10 years (due largely to aquatic mishaps) but a few lucky individuals have made it into their 50s. In his late 60s, Snooty was going strong and was an active, intelligent, and gregarious manatee until that cursed hatch failed. This makes one wonder how long manatees actually live when they don’t get run over with speedboats or eaten up by Portuguese conquistadors (and it also leads to other troubling thoughts about humankind’s interactions with other living creatures). I interacted with the late Ivak the walrus and Grandpa the lungfish, but I never had the chance to see Snooty. Yet I am still upset by his loss. I worry about the future of animals in our ultra-competitive dangerous world where even the world’s most respected and well-cared for manatee can have a fatal accident in his own tank. Let us say farewell to poor Snooty and keep working to better the lot of his brothers and sisters in captivity and in the wild.

lazylungfish.jpg

Sad news mars this bleak wintry day.  The Shedd Aquarium’s beloved Australian lungfish “Granddad” has passed away.  Granddad enjoyed basking sluggishly in his shallow pool until he beguiled viewers into not paying close attention to him, then he would rise to the top of his puddle and take a deep gasping (and very audible) slurp of air.  Lungfish are said to be among the most endearing of pet fish and Granddad enjoyed it when aquarium keepers gently petted him. He also loved eating a nutritious vegetable paste or clams or shrimp… although his particular favorite was “worm Wednesday”.  His diet changed several times during his tenure at the aquarium, as keepers learned more about how to look after him and as standards for lungfish husbandry progressed.   In his early days, he ate crayfish gathered from the pond in a local Chicago cemetery!

Grandad2.jpg

With his muscular pectoral and dorsal fins, Grandad was quite magnificent, in a torpid way–like an intelligent cucumber spattered with mud and gold.   At the time of his passing, he was the oldest fish in any public zoo or aquarium in the world.  Shedd acquired him (as a full grown adult) in 1933.  After a lengthy trip across the Pacific, he traveled across the United States in 3 days in a specially outfitted life-support railroad car.

2- Grandad vintage.jpg

A revealing historical passage from the Shedd aquarium’s lengthy and moving obituary describes the excitement over Granddad’s acquisition, “In anticipation of overflow crowds from the soon-to-open Century of Progress International Exposition just south of Shedd, aquarium director Walter Chute had written to the director of the Sydney aquarium with a wish list of fresh- and saltwater species. ‘We are, of course, particularly desirous of securing one or two specimens of Neoceratodus forsteri,’ he wrote, using the lungfish’s scientific name.”

55080-004-189D5919.jpg

Although these days I am closer to the African lungfish who live at the Bronx zoo, I saw Grandad back in the 90s when I lived in South Chicago and I was duly impressed by him.  Indeed, in a memorable conversation during college, a group of my closest friends and I were talking about what we would wish to have as accessories if we were action figures.  Although my buddies came up with lots of cool plasma guns, miniature vehicles, and humorous inside joke items, I feel I won the conversation by saying “lungfish.” Reading about Granddad only reinforces this feeling (although possibly these days, the “Wayne” action figure would have an avant-garde flounder rather than a clever lungfish).

aul-main-1.png

Although Grandad was only around a century old when he left this world, lungfish have been here a lot longer.  The sarcopterygians are nearly 350 million years old.  Living Sarcopterygians include only the coelocanths and lungfish (although all amphibians, reptile, birds, and mammals descend directly from them and could arguably be considered Sarcopterygians).  After 8 years of writing, I have been running out of things to say about catfish.  Once again, Granddad reminds me that there is an even wider and crazier world of fish out there.

tetrapod_evo.jpg

For example, did you know that lungfish have the largest genome among the vertebrates?   It takes a lot more information to produce a “Grandad” then it does to make Einstein or Rihanna!  Although we will miss our long-lived friend (and his mate, who died in 1980), he is survived by a passel of younger Neoceratodus forsteri, who can still be visited at the aquarium.  Additionally the Australians are very protective of their dear lungfish.  Although they are rare, the government watches after their habitat  quite carefully.  With any luck the lungfish in the Shedd aquarium will be around another 84 years, and the ones in Queensland will last another 350 million.  Maybe we can take them with us to the stars and start some entirely new tetrapod lineages!

6763f1dc2c1dc5099523d365eb108d3c.jpg

Ye Olde Ferrebeekeeper Archives

October 2017
M T W T F S S
« Sep    
 1
2345678
9101112131415
16171819202122
23242526272829
3031