RAVENSWOOD MEDIA NEWSLETTER

Issue #4, March 2008

Providing a conduit between science and the public

THE ARAL SEA DISASTER: LESSON FOR THE GREAT LAKES
By Nikolay Aladin, Contributing authors; Dr. I. Plotnikov, Prof. P. Micklin

The Aral Sea disaster is one of the gravest environmental calamities of the 20th century. In 1960, this brackish water body was the world's fourth largest lake in surface area and supported a thriving commercial fishery as well as a substantial maritime trade. By the mid 1980s, the Aral had severely shrunk and salinized, the commercial fishery collapsed and all marine transportation ceased.

Former seabed of The Aral Sea

The third period was in 1971-1976. That period was connected with the beginning of desiccation and salinization of the Aral Sea. At that time fresh water species adapted to the brackish water of the Aral Sea disappeared when water salinity exceeded 12-14 g/l.

The fourth period was in 1986-1989. That period was connected with the continuing desiccation and salinization of the sea. During this time, saltwater species of Caspian origin disappeared when water salinity exceeded 23-25 g/l.

The fifth period was in 1999-2003. That period was connected with the catastrophic desiccation and salinization of the Large Aral Sea. At that time the marine species became extinct when water salinity exceeded 80-100 g/l. The only species to survive this final stage were the salt-tolerant hyperhaline organisms.

In 1988-1989 the Aral Sea, due to desiccation, split in two parts: the Small Aral Sea in the north and the Large Aral Sea in the south. Instead of one ecosystem, two sister lake ecosystems were formed. The Small Aral has had a positive increase in water quality since its separation from the Large Aral Sea.

Rehabilitation of an aquatic ecosystem of the Small Aral Sea will be possible with the new concrete dam in Berg's strait which has led to a significant increase (up to + 42.5 m) of the water level and its biodiversity. Its average salinity has dropped to 10-12 g/l.

The Large Aral Sea continues to have negative water balance (its salinity is constantly going up and its level is going down). Rehabilitation of the aquatic ecosystem of the Large Aral Sea is not possible. The only possible maritime business is the harvesting of brine shrimp cysts. In 2004-2007 the Large Aral Sea separated into three water bodies: The Eastern and Western and Tschebas Lakes. The new lakes all have hyperhaline aquatic ecosystems.

THE CALIFORNIA CONDOR REINTRODUCTION
By David Cottrell

The California Condor fills an important role in the ecosystem, because it acts as a scavenger, ready to play its part by eating the carcasses of dead animals it finds by gliding long distances.

In prehistoric times, the condor ranged from coast to coast across southern North America. Today, these birds exist only in small populations scattered across southern California and the Baja Peninsula in Mexico. This endangered species is one of the world’s largest birds, with a wing span measuring up to 9 feet and an ability to glide 60 miles per hour over vast ranges.

Mike Wallace with condor egg

Other threats faced by condors have included injury or death due to power lines, past problems with DDT pesticides preventing eggs from hatching, illegal hunting, and ingestion of human trash by nesting chicks.

Captivity programs aim to ensure the survival of the condor. “Efforts continue to genetically and demographically manage the birds in captivity to ensure healthy young through propagation,” Dr. Wallace says. “Release work and management of the free flying birds at release sites ensure continued support of the wild populations including West Nile Virus vaccinations and veterinary care. Continued study on the effects of lead poisoning and trash ingestion will aid in reducing those important mortality factors.”

Julio Mercado and Fernando Sanchez

Mexican veterinarian, Dr. Fernando Sanchez, also works with condors. He believes the wide-open spaces of Baja are ideal habitat for the condor. “Baja is not very populated so there are big areas with just ranches and plenty of room to soar. The difference between Baja and California is that California has a rapidly growing population and in Baja, where we find condors, there are very few people.”

Connecting people to the condor is important for environmental stewardship. Schools and conservation groups in Mexico are starting to promote monitoring programs, where going outside with a pair of binoculars to view these magnificent creatures will ensure interest and ultimately, survival.

STATUS OF UGANDA’S AMPHIBIANS
By Caroline Aguti

The state of amphibians in Uganda is poorly understood compared to other vertebrates. The field of herpetology, and in particular frogs, is relatively new here. In addition to myself, there are only two other people working on frogs in Uganda; Mathias Behangana and Stephen Kigoolo. Though amphibians are excellent indicators in assessing the biodiversity of an area, very few studies have been carried out and most of them have been restricted to collections in protected areas in southern and western Uganda. The current literature consists of works of Pitman, Schiøtz, Kigoolo, Vonesh, Tinsley, Pitman, Behangana, Arusi, Drewes, Vindum and Aguti.

In Uganda, over 19 genera and 98 species of amphibians have been documented, which accounts for about 2.1% of the world’s total number of amphibian species. The most common families are: Hyperoliidae, Ranidae, Bufonidae, Pipidae, Petropedetidae and Arthroleptidae.

Caroline Aguti in the lab at Makerere University

Most amphibian species recorded in Uganda are listed by the IUCN Red List as Least Concern because they are either in very wide distribution, tolerant to a broad range of habitats or presumed to have large populations. Some of the species such as: Xenopus fraseri and Hyperolius argentovittis have a restricted range but are common and abundant where they occur. Populations of some species such as Bufo maculatus are extremely abundant and are recorded in a variety of habitats.

However, due to the limited number of studies carried out in Uganda and limited expertise, conclusive decisions on amphibian conservation are not possible. The country has a rich potential for new amphibian discoveries.

Uganda’s National Environment Management Authority has recently included amphibians in its studies for the Environment Impact Assessment. This is a positive step in the government’s recognition of amphibians in its conservation plans. However, most Ugandans have little regard for amphibians because their economic value is not understood.

Caroline is a member of NatureUganda, www.natureuganda.org, which is the oldest conservation organization in East Africa. It was set up in 1909 as a scientific organization with the primary aim of documenting the diversity of wildlife in East Africa. The Society is a research, conservation and membership organization based on good governance, established to undertake conservation actions using scientifically proven methods for the benefit of people. Over the years, its activities have diversified to include conservation action, awareness raising and advocacy. NU is now the leading authority on the status of Uganda’s birds and their habitats. The Society aims at conserving species, habitat and site.

Emanuele Biggi stomach flooding a Yellow-bellied toad

WHAT’S UP WITH AMPHIBIANS IN ITALY?
By Emanuele Biggi

Amphibian declines are one of the biggest conservation concerns for researchers around the world. Many populations have totally disappeared in the last 20 years for a variety of reasons, including climate change, the rise of more aggressive parasites, the loss of habitat due to human activity and of course, a deadly combination of all these causes.

Currently, there are 40 amphibian species recorded in Italy, of which 19 are endemic (subspecies excluded) and live in restricted areas. Population trends of Italian amphibians have not been extensively studied, however, there is evidence of population decreases for a number of species including the Italian Firebelly toad, Bombina pachypus, and a subspecies of the European Spadefoot toad, Pelobates fuscus insubricus. Habitat loss is the main cause of amphibian population declines in Italy. Many freshwater habitats, including those created by humans, are disappearing. The reasons for the loss of wetlands are the same in Italy as for the rest of the world - expanding agriculture and the spread of urbanization.

Many conservation laws are insufficient. Attention should focus on connecting many small parcels into a larger protected area, specifically for amphibians. To say “you can’t collect or kill this species” without saying “you can’t destroy or change the habitat of this species” is simply useless. Even more useless is to say “in this pond there are interesting species” without caring that these species also need a suitable habitat around the pond.

The European Community has done a great deal to save habitats. However, my feeling is that in Italy a frog or a salamander doesn’t count for most people. The lack of an amphibian conservation culture is a most destructive force. It acts like a hammer, crushing Italian amphibian populations.

Conservation awareness is growing in Italy. I had the opportunity to participate in an advanced course on wetland conservation in Trieste, Italy conducted by Dr. Nicola Bressi. Dr. Bressi is the founder of “Tutori Stagni Trieste”, an organization dedicated to protect and build new wetlands in the eastern part of Italy. Continued conservation efforts will help to restore the health of Italian amphibian populations.

Rana italica