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Update: June 17, 2008 
ANIMAL WORLD By Pam Eastlick
By Pam Eastlick for THE DEEP on line
Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.

I ran across several interesting animal stories recently and thought I would feature them this week. Although our first story is about animals, it could seriously affect you next year when Lent rolls around again.

WHERE HAVE ALL THE SALMON GONE?

United States Secretary of Commerce Carlos M. Gutierrez has declared a commercial fishery failure for the West Coast salmon fishery due to historically low salmon returns. Hundreds of thousands of Chinook salmon typically return to the Sacramento River every year to spawn. This year, scientists estimate that fewer than 60,000 adult fish will make it back to the Sacramento River. "The unprecedented collapse of the salmon population will hit fishermen, their families, and fishing communities hard, and that is why we have moved quickly to declare a fishery disaster," Gutierrez said. "Our scientists are working to better understand the effects that ocean changes have on salmon populations. We are also working closely with fishing communities to improve salmon habitat in river systems to support sustainable fishing." The estimated 60,000 salmon are far below what's needed to sustain the population and the government has shut down the commercial ocean salmon fishery for all of California and most of Oregon to aid their recovery. Although the reasons for the sudden decline of the fishery are not completely understood, NOAA scientists suggest that changes in ocean conditions, including unfavorable shifts in ocean temperature and food sources for juvenile salmon, probably caused the enormous drop in numbers that would have comprised this fall's fishing season. Loss of freshwater habitat for salmon spawning, rearing, and migration to the ocean is a chronic problem that has made salmon populations more susceptible to the occasional poor ocean conditions. Coho salmon stocks off Washington and northern Oregon, while in slightly better shape, are still far below normal, and the government plans to substantially curtail commercial fishing off those areas as well. Hmmm. You don't suppose the real problem is too many people and not enough fish, do you? And now a couple of stories about some little animals. Really little, as in microscopic. Although these stories may not appear to affect you as directly as the disappearance of salmon from your grocery shelves, you never know. John Muir, perhaps the first 'ecologist' said "When we try to pick out anything by itself, we find it hitched to everything else in the Universe".
The Vanguard I satellite celebrates its 50th birthday this year. Its launch on March 17, 1958 from Cape Canaveral, Florida, culminated the efforts of America's first official space satellite program begun in September 1955. (Credit: NASA)

Although Vanguard fell silent in 1964, it continues to serve the scientific community. Ground-based tracking of the satellite provides data concerning the effects of the sun, moon, and atmosphere on satellite orbits as astronomers monitor how Vanguard's orbit changes over time. When it was launched 50 years ago scientists thought it could last as long as 200 years. Vanguard is in such a stable orbit, scientists have extended this estimate to 2000 years. Happy Birthday little grapefruit and many happy returns!

A LITTLE HERE, A LITTLE THERE

One of my favorite microscopic animals is the rotifer. They're big enough to easily see at low power, they move around but not so fast that they dart out of range and disappear, and they have those incredibly cool spinning crowns at the tops of their heads. I can watch rotifers go about their business for hours on end.

There are some seriously cool facts about rotifers too. There are NO males; apparently female rotifers decided eons ago that they would always have control of the remote. Although they are sexless, they may be more promiscuous than any other creature on the face of the planet. Scientists at Harvard University have recently discovered that the genomes of these common creatures are chock-full of DNA from plants, fungi, bacteria, and animals. Their research shows that genes can enter the genomes of rotifers in a manner fundamentally different from other animals where genetic material is exchanged solely from the mating of males and females.

In essence the researchers say that rotifers may acquire DNA by habitually disintegrating their genomes -- something these unusual animals do regularly when the puddles in which they are usually found dry up. The rotifers desiccate, and this desiccation fractures their genetic material and ruptures their cellular membranes. When it rains, the rotifers miraculously spring back to life and, readily reconstitute their genomes and their membranes. In the process of rebuilding their shattered DNA, though, they may adopt shreds of genetic material from other rotifers in the same puddle, as well as from unrelated species.

Not only have rotifers relaxed the barriers that prevent the uptake of foreign genetic material in other animals, they've even managed to keep some of these alien genes functional. The next step of the research is to find out exactly what the rotifers do with the alien material. Since they don't exchange genetic material sexually, and they are also extraordinarily resistant to radiation, rotifers would be cut off from the two major sources of acquiring genetic changes. Perhaps this foreign material is the rotifer's way of staying on the evolutionary bandwagon. There is a LOT we don't know about the most common things! And now we turn from an animal that never has sex to one that never grows up.

IT TURNED INTO WHAT?

One of the main factors that makes life on Earth possible are the countless hoards of microscopic animals and plants that are collectively called plankton. Although most of us think that plankton is there simply to feed the whales, these tiny creatures form the basis of the entire ocean food chain AND make virtually all your oxygen for you. If the plankton all die, humans will follow shortly thereafter. There are thousands and thousands of different species in this sea of life and one of these species has been the source of one of the greatest zoological mysteries for over a century. A small crustacean larvae called a y-larvae was discovered in 1899 and in the ensuing 100 years, no one has ever found an adult of these puzzling creatures, leading generations of marine zoologists to wonder just what y-larvae grow up to be. Researchers have recently reported that they may have finally found the answer. Y-larvae are found amongst marine plankton in oceans from the poles to the tropics.

They occur in dizzying diversity in coral reefs, and even though they are everywhere and similar to the larvae of barnacles, not one adult y-organism has been identified in over 100 years of considerable searching. Y-larvae are the only crustaceans with a taxonomy based solely on larval stages, but their great species diversity indicates that the adults play an important ecological role. So researchers in Denmark and Japan collected over 40 species of y-larvae from a site near Okinawa and exposed them to a crustacean molting hormone to encourage them to finally grow up. The free-swimming y-larvae shed their articulated exoskeleton, and became a simple, slug- like, pulsing mass of cells. From this dismaying outcome, the scientists concluded that the adults of y-larvae are parasites, but they have no idea what they prey on. Y-larvae are closely related to the barnacles, which also have some disgusting parasite representatives. The stage induced by the molting hormone is not actually adulthood but yet another larval stage that resembles a juvenile of a highly specialized parasitic barnacle. The great diversity of the y-larvae and the finding that they are most likely parasitic as adults hints at a major ecological role that future studies, both in laboratories and in the field will try to uncover. These finding provide a tantalizing glimpse of the solution to this 100-year-old riddle. And now to end with a slightly larger animal. Much larger.

AND YOU WERE WORRIED ABOUT THE COQUI

Whenever you introduce a new plant or animal to an environment where it can thrive, you usually get problems. Big problems. The brown tree snake has virtually eliminated bird song on Guam, and there was some real fear that the bird song would be replaced by yet another invader, the coqui (also spelled kokee), a tiny frog with an incredibly loud voice. However, it turns out that if you're small and tasty and announce your presence with a loud clear voice, the brown tree snake doesn't care if you're a bird or not, one of the few recorded instances when two wrongs really do make a right. It turns out that Guam is not the only place with snake problems. Southern Florida is under attack too, but not by the brown tree snake. They're being invaded by gigantic Burmese pythons. The University of Florida's Institute of Food and Agricultural Sciences has published a new fact sheet outlining updated python statistics and methods being used to find and eliminate the snakes. That document follows the February release of a U. S. Geological Survey climate map that shows (based on climate, not habitat) that pythons can potentially survive across the lower third of the United States. Pythons are likely to colonize anywhere alligators live, including North Florida, Georgia and Louisiana. So far, most of the snakes have been found in Everglades National Park, but they've moved beyond its borders, too: as far north as Manatee County. The Burmese python, native to Burma in Southeast Asia, is one of the world's largest snake species. The largest found in the Everglades was 16 feet long and weighed 152 pounds. The snakes also are apparently breeding and it's feared that complete eradication is already out of the question. The females store sperm and can produce fertile clutches of 60 to 80 eggs a year for many years. Here are some highlights from the fact sheet.

  • From 2002-2005, 201 pythons were captured or found dead in and around Everglades National Park. In 2006-2007, the number more than doubled, to 418. The population in the Everglades has been estimated at more than 30,000.
  • Since May 2006, trackers have found seven pregnant female snakes and one nest of eggs; one recently captured python had 85 developing eggs.
  • Since May 2006, trackers have found seven pregnant female snakes and one nest of eggs; one recently captured python had 85 developing eggs.
  • Autopsied pythons found in Key Largo contained the remains of the endangered Key Largo woodrat. Other species on the pythons' prey menu include rabbit, gray squirrel, fox squirrel, domestic cats, raccoons, bobcats, white-tailed deer, limpkin, white ibis and the American alligator.
  • Not only are pythons fantastic swimmers, they can cover a lot of ground, as well. Two pythons with surgically implanted radio transmitters were found to have traveled 35 miles and 43 miles.

Here's hoping these babies NEVER get loose here. All we need are 16-foot long snakes that weigh as much as a man! From the microscopic to the MACROscopic, from the ridiculous to the sublime. Science is endlessly fascinating. Cruise on over to the Deep Website at www.thedeepradioshow.com to learn more about these and many other topics. Enjoy!

MAKING IT WORK AGAIN

One of the real scary things that's been happening lately is that many bacteria species are becoming resistant to antibiotics. Now researchers have discovered exactly how a bug that causes pneumonia has become resistant to the antibiotic penicillin. The same research could also cause MRSA, (perhaps the most notorious 'superbug') to become vulnerable to penicillin again and help create a library of designer antibiotics to use against a range of other dangerous bacteria. Worldwide Streptococcus pneumoniae causes 5 million fatal pneumonia infections a year in children . In the US it causes 1 million cases a year of pneumococcal pneumonia in the elderly and about 7% of them die from it. This new research showed how Streptococcus pneumoniae builds its penicillin immunity and opens up many ways to disrupt that mechanism and restore penicillin as a weapon against these bacteria. MRSA (methicillin-resistant Staphylococcus aureus) is one of the most dangerous superbugs and finding a way to make more antibiotics work against it would be a really lovely idea. Cruise on over to the Deep Website at www.thedeepradioshow.com to learn more about space exploration, white whales, MRSA and many other topics. Enjoy!