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CONSERVATION
Freshwater biodiversity is highly threatened today - a fact that should
be on the mind of every serious aquariast. The natural habitats of
tropical freshwater fish are increasingly threatened by human
activities, and while at times the hobby has been been at odds with
conservation, the role of aquariasts in preserving species is growing in
importance.
As their natural habitats are lost, freshwater fish species are
disappearing. A Malaysian study found fewer than half of the 266
resident fish species, while more than 30% of Singapore's fish species
are thought to be extinct. Freshwater biodiversity is highly
vulnerable. Habitats tend to be largely discontinuous meaning species
cannot easily cross land barriers that separate lakes and watersheds.
Thus freshwater fauna is generally localized, static, and subject
changing conditions. Whereas terrestrial species simply migrate in
response to habitat changes, freshwater species must cope with
ecological and climatic changes in order to persist.
Freshwater habitats are facing an onslaught of threats from
deforestation, waterway modification and dam construction, the
introduction exotic species, pollution, and over exploitation.
Deforestation in particular has major consequences for species popular
in the hobby. Erosion and the loss of habitat can severely affect fish
populations. Similarly damaging, the introduction of non-native species
(exotics) can devastate the local fauna as in the case of the Nile Perch
in Lake Victoria which has caused the extinction of endemic
Haplochromines.
Collection for the hobby has had a direct impact on some species to the
extent that they have become locally extinct over parts of their
ranges. For example the Bala shark is highly threatened in its native
Sumatra and Borneo due to its popularity as an aquarium fish. In the
past the Bala Shark (Balantiocheilus melanopterus) was heavily collected
since it did not readily reproduce in captivity (this has changed as
Balas are now captivity bred in fish farms). To optimize exploitation,
collectors targeted breeding grounds where Balas congregate for mass
spawning. The removal of breeding adults coupled with loss of habitat
from deforestation significantly impacted local populations. Similar
over harvesting has been documented among characins and the Arowana.
Today the role of aquariasts in conservation is changing. As habitat
loss continues -- especially the destruction of tropical forests -- the
importance of aquariasts in conservation is expanding. Aquariasts are
helping to maintain species (such as Cherry barbs and certain Killifish)
that are essentially extinct in the wild. By keeping these species and
populations viable, the fish-keeping community is protecting against
extinction. When and if reintroduction to natural habitats becomes
possible, it will be in part thanks to aquariasts.
Time has effectively run out for many species. Aquariasts can do their
part in preventing the further extinction of some freshwater fish.
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Recent news
Census of marine life opens with 122,000 species
(7/1/2008) Discovering a new species can be the highlight of a biologist's career. Yet once a species enters the formal literature, complications may develop. The systen has been especially problematic because for centuries biologists have lacked the tools to construct a full and flexible list of the world's innumerable species. Using the Internet and hundreds of scientists around the world, the Census of Marine Life is attempting to take on this monumental task.
Large shark populations fall 97% in the Mediterranean
(6/12/2008) Populations of some shark species in the Mediterranean have plunged by more than 97 percent over the past 200 years, report researchers writing in the journal Conservation Biology. Several species are at risk of extinction.
Dried-up Colorado takes toll on giant Mexican fish
(6/8/2008) The Colorado River vanishes before it reaches the Sea of Cortez in all but the wettest years. Companies in California and the southwestern U.S. have diverted its once-vibrant flow to quench their thirst for water and power. Now, a new study in the April 2008 issue of the journal Biological Conservation reports that the dwindling of this major artery has changed the way some marine fish in the Gulf of California grow and develop.
Diversity in streams may brace Chinook salmon for climate change
(6/3/2008) Chinook salmon face a one-two punch. They have disappeared from several rivers in the western U.S. largely because of human interventions and some populations are threatened or endangered. Numbers of Chinook in California's Central Valley have dwindled by 88 percent in the past five years, a loss that closed fisheries for 2008 and may cost California's economy $167 million, according to the state Department of Fish and Game. On top of all this looms a second impact: These salmon will be in hotter water still because of climate change.
Greenpeace ship attacked by Turkish tuna fishermen during protest
(5/30/2008) Members of a Turkish tuna fishing boat attacked the Greenpeace ship Arctic Sunrise while the ship was engaged in a protest against overfishing. The incident occurred Friday in the Cypriot Channel and was reported to the Turkish Iskenderun Gulf Port Authorities.
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