Monday, October 29, 2012

Maude Delap: Jellyfish Goddess of the North Atlantic

Maude Delap. Jellyfish Goddess of the North  Atlantic

Maude collecting with two of her sisters on Valentia Island. 

These days, I'm in the midst of writing a chapter on keeping jellyfish alive in the laboratory for nerve physiology experiments.  After months of research in American scientific journals, I was basically set to write this story of Sisyphean struggle to maintain jellyfish in marine laboratories.  Man, this is hard work- they just don't want to swim, or eat or grow in captivity. I can just imagine my historical actors tossing their exasperated hands in the air in a bizarre parody of the Eureka! moment.  Replace "eureka" with something like "Bullshit" or "this is impossible" or try "I give up!" and you might come up with a more true-to-life scientific scene involving maintaining jellyfish in captivity before 1930.  And seriously, I feel for these people. Jellyfish didn't really want to concentrate.  They sting, they die, they turn into balls of smelly goo, and they don't have eyes or noticeable features so giving them a talking to is out of the question. It was a chapter about skirting scientific failure, and then, I found Maude.

Maude Delap was a naturalist's naturalist. Born in 1866, she was the 5th of 10 children, all interested in the natural world.  When she was 8 years old, her father (a reverend) moved the family to Valentia Island- a point in County Kerry off the extreme South West end of Ireland.  Always interested in the marine environment, her collecting was boosted by a visit to Valentia from E.T. Browne and other investigators from the Plymouth research station in England.  Delap was mentored by Browne (who was actually a bit younger than her but formally trained) and continued her work with jellyfish long after he left Valentia.

And, her work was fruitful.  Because Delap did something that Browne and other marine investigators could only dream of: she successfully raised jellyfish through larval into medusae forms in a home aquarium!

I'm sure you're not as excited by this as you should be (or I am).  This could come from two points of confusion:
1. what are the forms of medusae?
2. why is it important that she did this?

Jellyfish, which scientists commonly refer to as medusae, are the free swimming sexually mature part of the life cycle.  We see jellyfish and we think, oh- that's what a jellyfish looks like.  But have you ever thought about what a baby jellyfish looks like? It doesn't look like an adult form at all, in fact- it has it's own name!

This illustration is the lifecycle of obelia jellyfish.  The tree-like organism on the left side of diagram is called a polyp (this is probably a group of polyps formed asexually by strobilation). The polyps eventually release free swimming medusae, which need to grow to mature size. So why does this life cycle matter and why does Maude matter?

Because you can catch a medusa, a planula, and you can also find a hydroid. You can collect them from the sea and plunk them into an aquarium.  And chances are- you might get the medusa to produce eggs and sperm to create a planula. You might even get a planula to metamorphoze into a hydroid. And you might get a  hydroid to release a tiny medusa. But, you're not likely to get all of these.  Cultivating medusae through their whole lifecycle is super super hard. It's a finnicky beast.  It likes its water just so (and that changes from season to season). It likes its food just so (and that changes depending on what part of the life cycle its in).

Between 1899 and 1900, Maude Delap did it.  And she did it awesomely.  On June 21, 1899 she picked up an injured Chrysaora Isosceles off the beach.  She took it home and put it into her tank, and by the next day, she found  planula free floating.  They attached themselves to the tankside and were kept as small hydroids throughout the winter.  While many believed that invertebrates feed primarily on copepods and plankton, Delap found that in this stage, they preferred feeding on the panula of other jellyfish, especially sarsia.  By spring, she had small medusae and by May they reached full adult size with 24 tentacles. Unfortunately, the weather turned foul and Delap was unable to keep providing her beauties with their preferred food (including small fishes- something else the scientific community doubted jellyfish ate). They lost weight and eventually died.

Delap's work is still cited in major laboratory manuals on how to raise jellyfish. It's clearly written, and Delap states very clearly why she made the choices she did, the temperature and placement of her aquarium, her feeding strategies, and every other aspect of her work that would allow someone to copy it for future experiments. Published in The Irish Naturalist in 1901, it is so awesome.

Dorothy Cross, an artist, produced some artwork inspired by Delap in 2001. Below, find a link to her artwork and an awesome interview about Maude Delap's work from the BBC's Woman Hour:

Dorothy Cross | Artists' stories | Artists talking | a-n

Maude Delap just changed the tenor of my chapter. Eureka!

Friday, October 26, 2012

'Wolf' Salmon

The blog entry above looks at efforts to protect "river wolves"- 100+ lb salmon (not to be confused with Peruvian otters and Canadian River Wolves) found in China, Russia, and Mongolia.  These huge fish take years to mature, and breed very slowly, making them an especially vulnerable species to over fishing and loss of habitat. They exist in pretty remote areas, so studies have been limited, but it's believed that these fish can live 30+ years.

These animals are just now listed on the "Red List"- which is an international watch list of species that are in peril and need to be watched more closely.  Being included on the list doesn't necessarily do anything to protect the fish, but this blogger seems to think it's a step in the right direction.

In truth, it's hard to know how many fish species should be included under the category "endangered" or "threatened" because we know so little about underwater creatures. Fish are notoriously hard to count, and deep sea species, or species that exist in remote areas such as the river wolves, are hard to count. Almost as difficult, is to judge their current numbers against a baseline (or point of reference) for comparison.  If you see some fish now, how many might you have seen 10 years ago? 15 years ago? 100 years ago? For many species, this data just does not exist.

For an idea about how investigators establish baselines, take a look at this publication outlining the establishment of baselines for tropical fish in Florida reefs over a 20 year period. In this study, SCUBA divers visited established underwater points throughout the year. They visually counted and recorded the number and type of fishes they encountered.  This method is possible because of the clarity of water, but is not necessarily an option for establishing baselines for all marine organisms. It also presupposes manpower and access to areas that these animals visit.  For the other species, such as the "river wolves," investigators might pay more attention to folk stories or family histories of how many fishes were caught in the past.  While this might seem like a less precise measurement than the Florida study, it is a form of data that scientists can utilize to gauge population decrease over time.

It makes sense that many fish species don't show up on "endangered species" lists until there are few left. Even then, it's difficult to gauge the decimation of the actual population. But, we know that fish species, especially edible species, are consistently over fished and under protected. Let's hope inclusion on this list leads to conservation programs that bolster the population of huge fishes without alienating the native peoples that rely on them as a food source.

Friday, October 19, 2012

(un)Parallel Explorations: Deep Space and Deep Sea

As the last of the space shuttles find their homes in museums throughout the United States, it is interesting to think of the intertwined vision of deep space and deep sea exploration. The belief that exploring the sea is similar to exploring space is entrenched in our cultural understanding of the ocean. Play the clip above- the trailer for James Cameron's "Aliens of the Deep".  In the trailer, the deep sea is directly correlated to deep space.  And deep space exploration is easy according to Cameron:

"We need to take everything we know about deep sea exploration and apply it to space."

This is a particularly misleading comment.  It suggests that sea and space are similar, but it also suggests that we know bunches about deep sea exploration.  Enough, it seems, to apply it to space exploration.  But Cameron has jumped the gun: deep sea exploration isn't close to being ready for other applications. And, the constant application of the alien concept of space to deep sea exploration might actually be hurting the endeavor.  So, how are these two forms of exploration similar, and how are they different? Let's check it out:

Both outer space and deep sea carry a sense of "otherness" in cultural conceptions.  Obviously, this stems from a sense of unknown vastness- but it also contributes to a sense of sameness that might be misleading- deep space and the deep sea are definitely not the same thing. Our knowledge of the deep sea environment has been limited to dredging of the sea bottom (a very small portion of the sea bottom)- a technique that is just basically the most haphazard form of sampling available and which kills most of the animals before they ever reach the surface- to very limited deep sea dives in manned and unmanned submersibles. The earth's deep sea depths continue to offer scientists and the public surprises:  the odds of finding new species (besides insects) in the terrestrial environment are very low, but the expectation of finding new species in the ocean are very high. In truth, we still have a very limited idea about deep sea environments.  But this unknown does not equal unknowable (in the way that deep space is still years away from even technically capable of being explored).  Cultural conceptions of the sea may too closely resemble conversations people have about space.  If people are convinced that the deep sea is unknowable and too vast to be explored, how might this affect funding and ideas about exploring these depths.  The depths of the sea are accessible! But, we need money to get there- so how does deep sea exploration funding match up with space exploration?

There's been a lot of talk about space funding recently.  NASA is being cut back and the age of commercial space exploration is here.  But before this era, there was NASA- and it was a huge force with a lot of funding. So where does deep sea exploration fit in? There has never been a deep-sea NASA-like initiative.  In fact, although exploration of the ocean is older, it has been shuttled between many different agencies in the government, meaning that funding is never quite clear.  In a recent 3 part series, scientists at the blog called for an Ocean NASA (Which they call OSEA- Ocean Science Exploration Agency). part 1part 2, and part 3 Recently, funding for ocean exploration and research has been cut without the public acknowledgement.  (see the previous post on Alvin or Part 1 and 2 above for information on these cuts) So, budgets are being cut on NASA and ocean exploration- but ocean exploration had less direct funding in the first place. So, how are these cuts affecting exploration and research?

Space X launched its first commercial rocket to the International Space Station in early October.  But what's up with deep sea exploration? In March, James Cameron made a solo dive to the Mariana(s) Trench in the Deep Sea Challenger. The vehicle and the expedition were mostly funded by corporate and private money (including Cameron and Rolex).  And as exciting as it was for the general public, it raises some interesting questions: who has access to the information collected? is this a return to a class based scientific endeavor? And for me, a question: what does it mean that a filmmaker, instead of a scientist, was the first solo person to reach this deep sea environment and introduce it to a larger audience (he's making a 3D film of his dive)? As some people have said, it's actually safer for an unmanned submersible to descend to those depths.The only other individuals to reach these depths were Jacques Piccard and Don Walsh- two Oceanographers in 1960.

The DeepSeaChallenger- both images from National Geographic.

Does the work of James Cameron somehow perpetuate a belief of the deep sea environment as an environment that is more fictional than scientific?   Does his manned dive somehow perpetuate these somewhat misleading intersections between deep space and deep sea explorations?  Is this helpful to the scientific endeavor or just another way to give the public a vision of what they've come to expect?

It is time that deep space and deep sea exploration become unwound. It's really not serving marine science.  But how can we go about untangling the dual images of the extremely different endeavors?

Monday, October 15, 2012

The Eye of a Kraken is probably twice as big!

A few days ago, NPR reported  that a huge eye had washed up on Pompano Beach (very close to one of my hometowns: Plantation) and asked readers to guess what type of creature might have been the original owner of the giant peeper.

The answers to the question suggest that people are still pretty confused about what may or may live in the ocean's depths.  They run the gamut from:

-multiple types of whales
-giant squid
-A/The Kraken (I'm a bit confused about kraken. Are there more than one? Only one?) 
-Big Foot

Turns out- it's probably a female swordfish.  Scientists suggest that the bone around the eye suggest it is a fish (whale's actually have pretty small eyes).  The largest swordfish ever caught was 612 pounds.  Interestingly, it also appears that the eye was removed by a professional:  there are tool marks on the bone, suggesting that a fisherman tossed the eye back into the water after removing it from his/her catch. 

So- not extraterrestrial or inexplicable. But still, pretty cool. I'm guessing the Kraken eye is way bigger. Just saying. 

West African Seahorse filmed in the Wild

Wednesday, October 10, 2012

The Stocking of Lake Powell

It's fall break at the University of Utah, so my husband had the week off. We decided to  skip brave the long drive down to Lake Powell for a few days to check it out.  We entered the Glen Canyon National Recreation Area at Bullfrog, UT. Created by the Glen Canyon Dam in 1963 (although the Dam itself was not officially completed until 1977), Lake Powell is the second largest artificial lake in the United States.  It straddles the Utah and Arizona borders, and is generally a playground for those individuals with power boats, time, and gas money.  

Because we lacked the huge chunk of change to rent a power boat, my mate and I decided to kayak around a little.  We barely made a dent in our proposed plan (we wanted to see Moki Canyon) but we ended up bringing our kayaks ashore in a small, unnamed inlet somewhere north of Bullfrog.  While hiking around the shoreline, we noticed quite a few bass in the water. We knew that there were fish in the lake because of the sheer amount of sunburned fishermen "pre-fishing" for this coming weekend's Ultimate Bass Team Tour Tournament of Champions. In fact, a fishing boat came into our secluded canyon only moments after we noticed the fish, intent on their capture.  

Watching the age old battle between man and fish got me thinking about those fish and about the stocking of Lake Powell.  
a view of the lake from our little inlet
In 1962, authorities in Arizona and Utah decided that there should be fish in Lake Powell, and they went about looking into stocking the area with sport fishes. One particular hurdle to stocking the Lake was its location- there were only one access point to the Lake overland in 1963, and that point was scheduled to be flooded by the incoming water.  Officials in Utah and Arizona, in consultation with the United States Bureau of Sport Fisheries and Wildlife (created in 1956 as a section of USFW), decided that the best beat for stocking might be by plane.

Stocking bass in Lake Powell by air, 1963. 

In 1963, almost 4 million trout and 924,000 large mouth bass were dropped from a plane 300 feet from the surface traveling at approximately 100 miles per hour.  

The next year, the size of Lake Powell had continued to expand and the states requested another stocking.  In April 1964, the first drop of the season was made.  This time, more care was taken to acclimate the bass fry- the hatchery water was dropped from 73 to 54 degrees while the fishes were in the plane.  Each drop last about 25 seconds- distributing about 500 pounds of bass over about a mile of the lake's surface.  Fisheries biologists waiting on the Lake immediately seined for surviving fishes and pronounced the drops a great success, with little loss of life- even though the fish were in route to the lake for almost 5 hours before being dropped. 

As evidenced by the Bass Tournament coming up this weekend, the stocking of Lake Powell was successful.  In 1968, threadfin shad, a favorite meal to the large mouth bass, was stocked, making Lake Powell a great destination for sport fishing. 

But everything is not perfect in Lake Powell.  In 2002, six gizzard shad were reported in the San Juan arm of the Lake.  Since then, gizzard shad have spread throughout the entire lake.  While large mouth bass do feed on gizzard shad, they can only do so during the gizzard shad's juvenile stages.  Once the gizzard shad achieves its full size, the bass can no longer prey on these organisms.  Biologists believe that gizzard shad might eventually overtake and crowd bass in the Lake. 

Beyond concerns about the gizzard shad, conservationists have turned their attention to preventing the entrance of zebra mussels and New Zealand mud snails from Lake.  So far, their efforts have been successful, but if the gizzard shad is any indication, it will be an uphill battle to prevent the introduction of invasive species from the area.  Both of these invasive species are transferred on watercraft- the only way to get around this recreation area.  

For more information on the stocking of Lake Powell and fishing in the area, see National Parks Service information on Glen Canyon Recreation Area

"Lake Powell Stocking Story" by John Maxwell and Robert Thoesen in Progressive Fish-Culturistist Vol. 27 Issue 3 (1965) Lake Powell Fishing Information 

Wednesday, October 3, 2012

Misleading Nomenclature and the case of the Vampire Squid

Not the Scourge you're looking for...Image courtesy of MBARI
Pictures: Vampire Squid's Surprising Diet Revealed

Word is going around: the Vampire Squid is not what we thought!  Apparently, after the discovery and completely misleading naming of this creature, some people assumed that it was the "bloodthirsty scourge of the sea." What could you expect from an animal named Vampyroteuthis infernalis- roughly translated "the vampire squid from hell"? Obviously something has to be the bloodthirstiest scourgiest member of the marine community, and it's definitely not the manatee.  The Vampire Squid looks fierce; it could scourge the sea. Well, apparently it's the cleanliest, vacuuming-est sea creature.  It feeds on "marine snow"- dead stuff. It's the scourge of sea dust bunnies.

I'm kind of let down. And obviously so is the New York Times, National Geographic, and every other major news outlet that publishes "science news" because it's been big news for over a week. Over a Week! Extra Extra: Not the Scourge We Thought! So, why is it that this "news" is so newsworthy? This animal is weird looking! But not a killer! What?!

What should be the news:

No one really responds to the fact that this organism is so hilariously named (it's like the obese guy with the nickname tiny of the ocean population). And there doesn't seem to really be any conversations about the obvious concerns that could arise from imposing ideas about diet and disposition through taxonomic naming. What's up taxonomy? What's your purpose? I don't know. Why don't we ask Dung Beetles named after Romney, Cheney, and Bush.

The Vampire Squid was named in 1904, but is particularly difficult to study because it is a deep sea creature and they are difficult to remove from the depths alive (they are often crushed by pressure when trying to bring them onto ships and arrive dead), let alone to culture and study in marine laboratories. If you are lucky enough to get a pelagic species to live in an aquarium, it's equally as difficult to figure out what they eat, get them to eat, and figure out what is "natural" to the creature versus "aquarium based." Especially difficult with this creature, because it apparently feeds on something that is difficult to replicate in the aquarium setting
The first vampire squid probably looks like the rest of these specimens.  Labeled and stuffed into a specimen jar on a shelf next to thousands of others. 

Photos of the ichthyology collections of the National Museum of Natural History.  Museum Support Center, Suitland.  Author's personal collection.

But, it should beg the question: how do the names we give animals influence our conceptions about them? It's something to think about, especially when many deep sea specimens are scientifically identified by one specimen- possibly dead by the time it is even viewed by a human (as the first vampire squid most assuredly was), sketched or photographed, possibly represented by a DNA coding, preserved in alcohol and shelved with thousands and thousands of other single specimens.  Naming systems, based on single specimens, draw a picture of the deep sea that could be quiet different than reality.

So, how do we link these preserved, single specimens to the larger ocean community? And what role does taxonomy play in this linkage? More on this question next time...