Yucatan

Scientists specializing in the area of underwater archeology, have just unearthed what appear to be four complete skulls of the extinct Arctotherium – a kind of stout faced bear which vanished off the face of the planet over 11,000 years ago – 42 meters beneath the waves, in an underwater cave on the Yucatan Peninsula of Mexico.

The skulls, which measured between 25 and 30 centimeters, belonged to two adult bears – one male and one female – as well as two bears which had not yet reached adulthood. It is not known whether these bears were a family unit or not, and that answer is not likely going to be easy to find out from just the skulls of the bears. A team of scientists, led by Guillermo de Anda Alanis, from the Yucatan Autonomous University, unearthed these skulls when they were making a dive through the underwater caverns.

Along with the skulls of the bears, the team also uncovered the skeletons of five humans not too far away. As soon as the dating of the human skeletons has been completed, they will be able to ascertain if the two finds are related.

The discovery of the skulls will help to initiate a change of thinking when it comes to the biogeography of bears in the Americas – Arcotherium was believed to have only made its home in South America. The only living descendant of these prehistoric bears is the spectacled bear which makes its home in Venezuela.

Yucatan peninsula

A Mexican skeleton which was ritually laid to rest in a cave that was once devoid of water, lends clues as to first Americans.

The skeleton which was discovered was supposedly laid to rest more than ten thousand years ago. It is one of the oldest such skeletons in the Americas, and was found in an undersea cave along the Yucatan Peninsula in Mexico.

Back when the skeleton was laid to its final resting place, the region was mostly desert, and the skeleton could lend clues which may shed some light on how he first Americans arrived, and just who they were.

Just about eighty miles south of Cancun, the intricate system of caverns of Chan Hol, which means “little hole”, is like a deep valley along the coast of the Caribbean.

German cave divers back in 2006, swam a remarkable 1,800 feet into the dark treacherous underwater tunnels and, quite by accident, happened across the Ice Age human’s remains ad sent notice to the archaeologists located in the surrounding state of Quintana Roo.

Over the past three years scientists under the guidance of the director of the Desert Museum in Saltillo, Mexico, Arturo Gonzalez, have been poking around and documenting the bones in place, so as not to disturb the scene and lose any vital things which might be offered by the surroundings.

It’s really astounding to think of all the ancient marvels which lie in wait for us under the ocean waves, if only we strap on a scuba tank.

The red snapper population living in the Gulf of Mexico is showing signs of recovery, according to new information obtained by the National Oceanic and Atmospheric Administration of the United States (NOAA).

“The update showed harvest levels were still a bit too high in 2008; however, scientific projections are promising for 2009, indicating that the stock may improve enough to support higher harvest levels,” said Dr. Bonnie Ponwith, Southeast Fisheries Science Center director for NOAA’s Fisheries Service. “This is very exciting news and is evidence of how science and management can work together to protect our natural resources.”

In response to a rapidly dwindling red snapper population, the Gulf of Mexico Fishery Management Council began restricting red snapper fishing in the mid-1980s and in 2007 a catch share program was implemented for commercial fishermen.

“This has been our most challenging fishery issue in the Gulf of Mexico to date,” said Dr. Roy Crabtree, southeast regional administrator for NOAA’s Fisheries Service. “The Gulf Council deserves a lot of credit for making some very difficult decisions and commercial and recreational fishermen deserve equal credit for complying with the regulations to help this species recover.”

The red snapper in the Gulf of Mexico is managed separately from the population living along the coasts of North Carolina, South Carolina, Georgia, and eastern Florida. In December 2009, NOAA’s Fisheries Service announced a temporary rule to protect the red snapper along this coastline as the population is in poor condition, much like the Gulf of Mexico population used to be. The temporary rule will become effective today, January 4th.

For more information please see the NOAA News Release.

A gigantic underwater museum filled with 400 sculptures will be created in Mexico’s West Coast National Park in on the Yucatán Peninsula. The artistic director is Jason de Caires Taylor, famous for his underwater sculptures, but other artists will also be involved in the project.

The Subaquatic Sculpture Museum is designed to relieve some of the pressure placed on the regions natural reefs by divers and snorkelers; the national park currently receives almost 300,000 visitors each year and quit a few of these vacationers do not behave as careful around the reefs as they should.

“If they [the tourists] swim near the corals, the divers with little experience might kick them with a fin or hit them with the oxygen tank,” says national park director Jaime

González, adding that some tourists even climb coral reefs and walk on top of them, breaking and shattering them.

In 2005, the park administration submerged 110 hollow domes and concrete structures in layers in the Sac Bajo area in a similar effort to divert tourists from the natural reefs, and this project has already become a success story.

“At first the people of Isla Mujeres told us that they were never going to bring tourists there, but after a few years it became a must-see attraction,” says González.

The park administration is planning to launch the new underwater museum next month by submerging four sculptures in human form. All 400 sculptures in the museum will be made from pH neutral concrete to allow rapid growth of algae and incrustation of marine invertebrates, such as corals. Eventually, the new habitat will also begin to attract reef fish – just like the Sac Bajo project.

“The underwater museum will draw many tourists, allowing us to give a rest to the natural reefs. It’s like a restoration process,” says González.

If everything goes according to plan, some 250 sculptures will have been submerged by April 2010. Each sculpture will be human sized and rest on a four square meter base. Some parts of the museum will be theme based, such as the “Coral Collector” gallery and the “Dream Catcher” section which features bottles filled with messages sent by castaways. There will also be a series of sculptures depicting Maya warriors.

The gar family, famous for containing the largest fresh water fishes in Mexico, is currently at risk of becoming extinct – something which Mexican researchers are working hard to prevent.

“This fish is native to our country and the United States”, Doctor Eduardo Mendoza Alfaro explains. “Currently, its populations are threatened due to excessive hunting, — for there are no rules that regulate its fishing — urban expansion, pollution, and particularly the dams´ construction, which caused the destruction of their breeding grounds. These factors led this species to reduce to only forty adult specimens in the country — in inventory and considered national patrimony.”

Doctor Eduardo Mendoza Alfaro*, a member of the ‘Eco-physiology Group,’ from the Universidad Autonoma de Nuevo Leon’s (UANL) School of Biological Sciences Ecological Department, is currently researching gar reproduction and diet in order to find ways of efficiently raising gars in captivity. The team also works with several other types of endangered fish, but the gar – which can reach a length of three meter and is highly esteemed by sport fishers – is arguably the most iconic.

Lepisosteus platostomus – Shortnosed gar, Copyright www.jjphoto.dk

One of the hurdles that must be overcome to ease gar raising in captivity is how to distinguish males from females. In a reproductive facility you want to keep an ideal sex ration – with gars this is four males for each female – but this is difficult to accomplish without reliable sexing methods.

“We could not identify females and males, because, morphologically, they are

Identical”, says Dr Alfaro. “Even though most of the fish can be cannulated in order to know their gender and maturation status, for gar is not the same process, that is what represents

the first obstacle for scientifics when they were carrying out the reproduction

studies and establishing fish’s gender. Most of the fish can be cannulated by introducing them a catheter in the oviduct in order to take the oocytes (ovules). However, this process cannot

be carried out with the gar. They are so primitive fish, which date since 189 million years ago and their urinal tract which ends with the oviduct in a kind of sewer that cannot allow the

cannulation.”

To overcome the problem, Dr Alfaro and his team devised a new technique based on a molecule known as vitelogenine. Vitelogenine is present only in females from puberty and onwards, and can be used as a biochemical marker.

First, the team purified the molecule. Then, they created antibodies against the molecule for recognizing and quantifying it.

“Currently, we got an extremely sensitive method which allows us to dose this molecule with only a small sample of fish’s skin mucus, says Dr Alfaro. “So, we not only identified if it is a female or a male, but we can follow up females’ sexual maturation.”

Gar facts

· The gar family evolved during the cretaceous.

· A gar can weigh up to 220 lbs.

· The gar is a predatory fish with an elongated jaw. It is sometimes referred to as alligator fish due to its resemblance to the predatory reptile. It has numerous sharp teeth and a body protected by hard scales.

· Gars spawn in swamps during the wet season and destruction of wetlands poses a problem for them.

· In the wild, several males follow the female wanting to fertilize her eggs as she deposits them.

· Mexico is the world’s leading gar specimen producer.

*Roberto Eduardo Mendoza Alfaro is a professor at the UANL´s School of Biological Sciences Ecology Department in Leon, Mexico.

A 19.5 feet long squid – that’s almost 6 meter – has been caught in the Gulf of Mexico by a group of scientists from the NOAA’s* Southeast Fisheries Science Center and the Department of the Interior’s Minerals Management Service. This is only the second known giant squid caught in the Gulf of Mexico and the last one was collected 55 years ago.

The gigantic squid of 1954 was a dead specimen found floating around at the surface off the Mississippi Delta, while the 103 pound giant caught on July 30 this year was pulled up from a depth of more than 1,500 feet by NOAA’s trawling research vessel Gordon Gunter.

“As the trawl net rose out of the water, I could see that we had something big in there…really big,” said Anthony Martinez, marine mammal scientist for NOAA’s Fisheries Service and chief scientist for this research cruise. “We knew there was a remote possibility of encountering a giant squid on this cruise, but it was not something we were realistically expecting.”

“This is an incredibly rare find in the Gulf of Mexico,” said Dr. Michael Vecchione, director for NOAA’s Fisheries Service’s National Systemics Laboratory and a giant squid expert. “Giant squid have been found more commonly in areas of the world where there are deep-water fisheries, such as Spain and New Zealand, but this is the first time one has actually been captured during scientific research in the Gulf of Mexico.”

The capturing of the squid took place during a 60-day scientific study of sperm whale prey off the coast of Louisiana. The giant squid has now been preserved and sent to the Smithsonian Institution’s National Museum for Natural History.

*U.S. National Oceanic and Atmospheric Association

According to predictions made by a team of NOAA-supported scientists from the Louisiana Universities Marine Consortium, Louisiana State University, and the University of Michigan, the Gulf of Mexico “dead zone” is likely to become record big this summer. If there predictions are true, we will see a dead zone the size of New Jersey (7,450 to 8,456 square miles). Additional flooding of the Mississippi River since May can however increase these numbers even further.

What is the Gulf of Mexico ‘dead zone’?

The dead zone is an area off the coast of Louisiana and Texas in the Gulf of Mexico where the oxygen level seasonally drops so low that most life forms living in and close to the bottom dies.

Dead zones are the result of large amounts of nutrients reaching the water, e.g. through waterways polluted by sewage and agricultural runoff. The excess nutrients stimulate rapid and massive algae growth in the affected area, a so called algae bloom. When the algae die, they sink to the bottom where oxygen dependant bacteria begin to break them down. The decomposition process consumes vast amounts of oxygen and soon the bottom and near-bottom waters become so oxygen depleted that all sorts of oxygen breathing organisms begin to die. This so called hypoxic area (an area where the oxygen levels are low to non-existent) is not just a problem for wildlife; it can also damage the economy of nearby states since it destroys habitat necessary for commercial and recreational Gulf fisheries.

The largest dead zone on record appeared in 2002 and measured 8,484 square miles.

Mississippi and Atchafalaya Rivers too rich in nutrients

During April and May this year, the Mississippi and Atchafalaya Rivers experienced heavy water flows that were 11 percent above average.

“The high water volume flows coupled with nearly triple the nitrogen concentrations in these rivers over the past 50 years from human activities has led to a dramatic increase in the size of the dead zone,” said Gene Turner, Ph.D., a lead forecast modeler from Louisiana State University.

“As with weather forecasts, this forecast uses multiple models to predict the range of the expected size of the dead zone“, said Robert Magnien, Ph.D., director of NOAA’s Center for Sponsored Coastal Ocean Research. “The strong track record of these models reinforces our confidence in the link between excess nutrients from the Mississippi River and the dead zone.”

In a study announced today by the Wildlife Conservation Society* (WCS) at the International Coral Reef Initiative** (ICRI) meeting in Thailand, researchers show that some coral reefs located off East Africa are unusually resilient to climate change. The high resilience is believed to be caused by geophysical factors in combination with improved fisheries management in these waters.

After studying corals off the coast of Tanzania, researchers found that these coral reefs has made an incredibly speedy recovery from the 1998 bleaching event that wiped out up to 45 percent of the region’s corals. The authors of the study attribute the swift recovery to a combination of reef structure and reef management.

Compared to many other coral reefs around the world, Tanzania’s reefs are used to considerable variations in both current and water temperature which has turned these reefs into an unusually complex web of different coral species. This bio-diverse ecosystem includes several different species known to quickly re-colonize an area after a bleaching incident.

The authors of the study believe that reefs in other parts of the world subjected to similarly diverse environmental conditions might have the same high ability to recover from large-scale climatic and human disturbances. The study provides additional evidence that such “super reefs” can be found in the triangle from Northern Madagascar across to northern Mozambique to southern Kenya and the authors suggest that these reefs should be a high priority for conservation efforts since they may come to play an important global role in the future recovery of coral reefs worldwide.

“Northern Tanzania’s reefs have exhibited considerable resilience and in some cases improvements in reef conditions despite heavy pressure from climate change impacts and overfishing,” says Dr. Tim McClanahan***, the study’s lead author. “This gives cause for considerably more optimism that developing countries, such as Tanzania, can effectively manage their reefs in the face of climate change.”

The study also stresses the impact of direct management measures in Tanzania, including closures to commercial fishing. Algae is known to easily smother corals, but researchers found how areas with fishery closures contained a rich profusion of algae eating fish species that kept the corals clean. The few sites without any management measures remained degraded, and in one of them the population of sea urchins had exploded. Sea urchins feed on corals and can therefore worsen the problem for an already suffering reef.

The study has been published in the online journal Aquatic Conservation: Marine and Freshwater Ecosystems.

Authors of the study include Tim McClanahan and Nyawira Muthiga of the Wildlife Conservation Society, Joseph Maina of the Coral Reef Conservation Project, Albogast Kamukuru of the University of Dar es Salaam’s Department of Fisheries Science and Aquaculture, and Saleh A.S. Yahna of the University of Dar es Salaam’s Institute of Marine Sciences and Stockholm University’s Department of Zoology.

* The Wildlife Conservation Society is an institutional partner to ICRI and is actively conserving tropical coral reef species in priority seascapes in Belize, Indonesia, Papua New Guinea, Fiji, Kenya and Madagascar. Along with monitoring reefs, WCS also trains of park staff in protected areas.

** The International Coral Reef Initiative (ICRI) is a global partnership among governments and organizations working to stop and reverse the degradation of coral reefs and related ecosystems. This ICRI General Meeting was convened by the joint Mexico – United States Secretariat.

*** Dr. McClanahan’s research regarding ecology, fisheries, climate change effects, and management of coral reefs at key sites throughout the world is supported by the Western Indian Ocean Marine Science Association (WIOMSA) and The Tiffany & Co. Foundation.

A ROV (remote operated vehicle) owned and operated by the oil company Shell have caught video of a very rare squid while filming a mile and a half (two and a half kilometers) underwater on the drilling site known as Perdido in the gulf of Mexico. The squid known as a Magnapinna squid has a unique look due to the fact that it has “elbows” on its arms. Little is known about these enigmatic squids that can grow to be between 5 to 23 feet (1.5 to 7 meters) long.

See video – See pictures

A total of four species of these squids have been found so far but there are likely more species still waiting to be discovered.

Magnapinna pacifica was the first species to be described and was described in 1998 by Michael Vecchione of the U.S. National Oceanic and Atmospheric Administration (NOAA) and University of Hawaii biologist Richard Young based on juvenile squids. Michael Vecchione and Richard Young later released a report that showed that Magnapinna squids are common in deep sea areas around the world. (Below about 4,000 feet (1,219 meters).)

The second species, M. talismani, was described in 2006 and the year after a third species M. atlantica was described. Both these species have been found in the Atlantic.

The last known species has yet to receive a scientific name.

Deteriorating water quality, invasive species and the practise of draining lakes is now bringing the axolotl, a neotenic mole salamander native to central Mexico, to the brink of extinction. According to researchers the species could disappear in just five years and it is currently listed as Critically Endangered on the IUCN Red List of Threatened Species.

“If the axolotl disappears, it would not only be a great loss to biodiversity but to Mexican culture, and would reflect the degeneration of a once-great lake system,” says Luis Zambrano, a biologist at the Universidad Nacional Autónoma de México (UNAM).

The axolotl (Ambystoma mexicanum) is native to no more than two lakes, Lake Xochimilco and Lake Chalco, and Lake Chalco was drained in the 1970s to prevent flooding. The only surviving wild population of axolotl is therefore to be found in Lake Xochimilco; a lake that is rapidly vanishing due to draining efforts. Today, Lake Xochimilco can not even be accurately described as a lake anymore; it is just a series of canals and scattered lagoons. As if this wasn’t bad enough for the axolotl, this salamander also has to combat severe pollution and the introduction of alien species. Mexico City has been pumping its wastewater into the remains of Lake Xochimilco since the 1980s, and both African tilapia and Asian carp have been deliberately introduced to serve as food fish. These alien species compete for prey items with the axolotl and are also fond of eating its eggs.

The exact number of axolotls left in the wild remains unknown, but a survey conducted by Zambrano shows a sharp drop from roughly 1,500 specimens per square mile in 1998 to no more than 25 per square mile in 2008.

One way of improving the situation for the remaining axolotls may be to create a series of axolotl sanctuaries in canals cleared of invasive species, but this would of course require some type of barrier to keep the aliens from returning. A pilot sanctuary is planned to open in Mexico City in 2009.

Repopulating Lake Xochimilco with captive reared specimes has also been suggested, since the axolotl is a popular house pet known to readily breed in captivity. Unfortunately, it is always risky to re-introduce a species into the wild since captive specimens may be carriers of genetic problems or hosts of malicious organisms like parasites, viruses and bacteria.

During the Aztec empire, the axolotl was an important food item as well as an integral part of numerous myths and legends. According to legend, the Aztec god Xolotl – who was in charge of death, lighting and monstrosities – suspected the other gods of plotting to banish or even kill him, and turned himself into a salamander in order to fool them. He moved to Lake Xochimilco where he could stay hidden from the other gods and Xolotl became a-xolotl, blessing the Aztecs with an important source of food. If you visit markets in Mexico City today you can still find axolotls being sold as food. Cooked axolotl is however becoming a more and more scarce dish on Mexican dinner tables, mainly because fishermen almost never find them.

Outside Mexico, the axolotl is more popular as a pet than a snack. It can today be found in pet shops world-wide, sometimes being offered under other names such as Wooper Rooper or Mexican Water Monster. The axolotl is also famous for its ability to regenerate most body parts and is extensively used in scientific research on regeneration and evolution.