Posted on February 12, 2014 by Bob Berwyn
Global warming threatens equatorial fish populations.
Many equatorial fish species already living close to their thermal limits
By Summit Voice
FRISCO — Global warming could put many equatorial species of fish at risk, according to scientists who studied six common species of fish living on coral reefs near the equator.
“Our studies found that one species of fish could not even survive in water just three degrees Celsius warmer than what it lives in now,” says the lead author of the study, Dr. Jodie Rummer from the ARC Centre of Excellence for Coral Reef Studies at James Cook University.
Rummer said many species in this region only experience a very narrow range of temperatures over their entire lives, and so are likely adapted to perform best at those temperatures. This means climate change places equatorial marine species most at risk, as oceans are projected to warm by two to three degrees Celsius by the end of this century. Continue reading
Filed under: biodiversity, climate and weather, Environment, global warming | Tagged: climate change, equatorial fish, fish, global warming | Leave a comment »
Posted on April 6, 2013 by Bob Berwyn
Chinese fleet takes 12 times more fish than it reports
A new analysis shows where China catches its fish.
By Summit Voice
SUMMIT COUNTY — Illegal fishing is a persistent problem, but it appears that China has elevated it to a new level, catching about 12 times more fish than it formally reports to the United Nation’s Food and Agriculture Organization, an international agency that keeps track of global fisheries catches.
Overall, Chinese fishing boats catch about US$11.5 billion worth of fish from beyond their country’s own waters each year according to a new study led by fisheries scientists at the University of British Columbia.
“China hasn’t been forthcoming about its fisheries catches,” said Dirk Zeller, a senior research fellow with UBC’s Sea Around Us Project and the study’s co-author. “While not reporting catches doesn’t necessarily mean the fishing is illegal … we simply don’t know for sure as this information just isn’t available,” Zeller said, explaining that there could be agreements between China and other countries that allow unreported fishing. Continue reading
Filed under: biodiversity, Environment, Marine biology, ocean conservation, Uncategorized | Tagged: China, fish, Food and Agriculture Organization, illegal fishing, ocean conservation, University of British Columbia | 1 Comment »
Posted on February 17, 2013 by Bob Berwyn
It is difficult to be a fish when the bottom of the river is covered with ice. Winter image from the river Orkla in Norway. Photo courtesy Knut Alfredsen.
Most existing models are geared toward ice-free periods
By Summit Voice
FRISCO — Norwegian and Swedish biologists have taken a closer look at how extreme winter conditions in streams and rivers in cold regions, with an eye toward climate change models that predict more frequent variations between freeze and thaw conditions.
“Today most models focus on the ice-free period … In order to be able to manage streams and rivers in a long-term sustainable manner, we need to pay attention to future changes in climate when we, for example, design restoration and conservation measures, the researchers wrote in a new paper published this month in the journal BioScience.
“The predictions made about what the winter climate will be like in the future say that there will be more back and forth between thaw and frost, entailing more unstable ice conditions, more rain, and flooding, and ultimately perhaps more challenges to the survival of fish in many waterways,” said Christer Nilsson, of Sweden’s Umeå University. Continue reading
Filed under: biodiversity, climate and weather, Environment, global warming, rivers, water | Tagged: BioScience, climate change, fish, rivers, Sweden, Umeå University | Leave a comment »
Posted on August 10, 2012 by Bob Berwyn
The Colorado pikeminnow has been extirpated from Nevada. Photo courtesy Nevada Natural Heritage Program.
Modern era rate of extinction more than 800 times higher than background rate over geological time
By Summit Voice
SUMMIT COUNTY — Habitat loss and the spread of invasive species have led to an”alarming” increase in the rate of extinction among North American freshwater fish, according to a new study by U.S. Geological Survey researcher Noel M. Burkhead, who documented fish populations going back to the late 1800s.
The rate of extinctions increased noticeably after 1950, although it leveled off in the past decade. The number of extinct species has grown by 25 percent since 1989, Burkhead wrote in a study published in the September issue of BioScience. Continue reading
Filed under: biodiversity, endangered species, Environment | Tagged: aquatic life, Background extinction rate, biodiversity, endangered species, fish, Habitat destruction, North America | 1 Comment »
Posted on July 31, 2012 by Bob Berwyn
Southwestern Colorado trout fishery threatened by bass
Smallmouth bass illegally introduced to Colorado waters threaten native fish.
SUMMIT COUNTY — Bucket biologists are causing more headaches for Colorado wildlife managers by illegally stocking fish, including smallmouth bass at Miramonte Reservoir in San Miguel County.
Colorado Parks and Wildlife is now planning to eradicate smallmouth bass by using an organic pesticide to kill all the fish in the reservoir and then rebuild this renowned trout fishery that attracts anglers from throughout the West. The operation is tentatively scheduled to occur in late summer or fall of 2013.
Along with threatening trout in the reservoir, the smallmouth bass are also a potential threat to three native fish species: Roundtail chub, the bluehead sucker and the flannelmouth sucker
In the meantime, Parks and Wildlife is implementing an emergency order that removes all bag and possession limits on smallmouth bass at Miramonte Reservoir.
“Killing all the fish in the reservoir lake is something we wish we didn’t have to do, but we know we must,” said Renzo DelPiccolo, area wildlife manager in Montrose. “People who illegally move fish into lakes, ponds and rivers are not only committing a criminal act, they are endangering native species, stealing a resource and recreational opportunity from thousands of anglers and negatively impacting the local community.” Continue reading
Filed under: Colorado, Colorado Division of Wildlife, Colorado State Parks, fishing, recreation | Tagged: Colorado, endangered species, fish, fishing, native species | Leave a comment »
Posted on July 12, 2012 by Bob Berwyn
A red shiner.
Hormone-mimicking chemical could result in inter-species breeding
By Summit Voice
SUMMIT COUNTY — Already pinpointed as a potential health risk to humans, the controversial chemical BPA has now been found to affect the mating choices of fish. potentially leading to inter-breeding of species.
BPA, used in the manufacture of plastic household products, is hormone-mimicking chemical now widely found in aquatic ecosystems across the U.S. The chemical has been banned from baby bottles and childrens’ cups in 11 states. Continue reading
Filed under: biodiversity, Environment | Tagged: aquatic ecosystems, BPA, Environment, fish, hormones | Leave a comment »
Posted on June 22, 2012 by Bob Berwyn
Wildlife managers implement voluntary fishing closure on the Yampa
Some Colorado rivers and streams will take a hit from the drought this summer, but fishing should be fine at high elevation reservoirs like Clinton Gulch.
By Bob Berwyn
SUMMIT COUNTY — During what should be the peak of the runoff season, some of Colorado’s streams and river are already on life support, including the Yampa River in Steamboat Springs, where state officials have asked anglers to observe a voluntary fishing closure.
The closure will be in effect from the upstream boundary of the Chuck Lewis State Wildlife Area downstream through the city limits of Steamboat Springs, and anglers are asked to avoid this area.
Ron Velarde, regional manager for Colorado Parks and Wildlife, said the closure is voluntary for now and anglers are asked to avoid fishing there during the hottest part of the day, or preferably, to fish in other areas. If conditions worsen and several criteria established by regulation are met, a strict emergency closure enforced by law may become necessary. Continue reading
Filed under: climate and weather, Colorado, Colorado Division of Wildlife, Drought, Environment, rivers, water | Tagged: Blue River, Colorado, Colorado River, drought, fish, rivers, Yampa River | 1 Comment »
Posted on May 3, 2012 by Bob Berwyn
‘The oil is not gone yet. This disaster is not over. There are embryos right now that are still getting exposed to that oil.’
Zebrafish. PHOTO COURTESY THE WIKIMEDIA COMMONS.
The Deepwater Horizon oil drilling platform after the April 2010 explosion. PHOTO COURTESY U.S. COAST GUARD.
By Bob Berwyn
SUMMIT COUNTY — Oil from the Deepwater Horizon disaster causes very specific and potentially lethal defects in fish, including heart problems and loss of facial cartilage.
The oil also prevents fish from swimming away from danger, probably because of damage to sensory neurons, according to a study published this week in BioMed Central’s open access journal BMC Biology.
In a controlled lab setting, Dr. Michael Barresi and his students at Smith University in Massachusetts exposed zebrafish (a common freshwater fish often found in aquariums) to concentrations of oil that probably still exist at similar levels in the gulf today, two years after the Macondo Well spewed millions of gallons of crude oil into the Gulf. Continue reading
Filed under: biodiversity, BP Gulf oil spill, Environment, Marine biology, oil drilling | Tagged: Deepwater horizon oil spill, developmental defects, Environment, fish, Gulf of Mexico, Macondo oil, marine biology, Oil spill | 5 Comments »
Posted on August 17, 2011 by Bob Berwyn
Native fish doing well in new home
Cutthroats are the only trout species native to Colorado. PHOTO COURTESY COLORADO PARKS AND WILDLIFE.
By Bob Berwyn
SUMMIT COUNTY — Last summer’s Medano Creek wildfire burned about 6,000 acres in the mountains above Colorado’s famed sand dunes, but land managers in the national park and the adjacent national forest didn’t wage an all-out war against the flames.
The lightning-sparked blaze didn’t threaten any structures, so firefighters established a generous containment perimeter and let the fire burn within the area, consuming dead and downed trees and old, mature conifers.
In the long run, some the burned areas may be repopulated by aspen trees, while other areas may revert to meadows. The newly patch-worked landscape may be less susceptible to large-scale catastrophic fires in the future, park managers said.
But Medano Creek watershed is also home to rare cutthroat trout, an endemic species in the San Luis valley and the only trout species native to Colorado. Even before the fire was out, fisheries experts moved to protect the fish from potential impacts. Continue reading
Filed under: biodiversity, Colorado, Environment, forest fires, forests, rivers, Summit County news, wildlife | Tagged: Environment, fish, Medano Creek, Rio Grande cutthroat trout, Summit County News, Trinchera Ranch, wildlife | Leave a comment »