Brook trout in Red Run down to zero
Warmer temps, deforestation to blame
By Bryna Zumer
bzumer@patuxent.com
Posted 10/15/08
Warmer temperatures and deforestation have apparently contributed to a decline in brook trout in Maryland streams, including Red Run in Owings Mills, according to a recent study.
Scott Stranko, a biologist with the state’s Department of Natural Resources, spearheaded the study, which was published online in August by the North American Journal of Fisheries Management.
The study looked at the correlation of brook trout with water temperatures and land cover in six Baltimore-area streams over the past 30 years.
Although Red Run did not have much brook trout to begin with, it now seems to have none at all. The study says the density of trout per square meter in the stream, which ranged from 0.001 to 0.006 in the 1980s, has dropped to zero since 1990.
“Historically, Red Run had brook trout in the headwater section and, to my knowledge, they are no longer there,” said Mark Staley, an inland fisheries biologist with the state department.
Other Baltimore County streams studied include Baisman Run, Timber Run and Sawmill Branch.
Meanwhile, the amount of impervious land in the area, such as roads, parking lots and buildings, has grown and the amount of forested land has declined.
Brook trout require very clean, high-quality streams and prefer water temperatures of less than 60 degrees, which may explain why they are dying out or leaving Maryland.
Red Run’s average maximum daily temperature in 2005 was 73 degrees and could reach 77 degrees.
“Everything (humans) do in the watershed typically increases water temperature,” Staley said.
Stranko said the drop in their numbers is a loss for the state.
“Brook trout is our only native trout species,” he said. “It’s important to sportsmen. It’s important to people concerned with biodiversity. It’s sort of our iconic species.”
Brown trout, which is common nationwide, is now much more prevalent than brook trout in Maryland streams, he said.
“It’s the homogenization of our environment and, to me, that is very tragic because we are losing what makes these places special.”
Scott Stranko, a biologist with the state’s Department of Natural Resources, spearheaded the study, which was published online in August by the North American Journal of Fisheries Management.
The study looked at the correlation of brook trout with water temperatures and land cover in six Baltimore-area streams over the past 30 years.
Although Red Run did not have much brook trout to begin with, it now seems to have none at all. The study says the density of trout per square meter in the stream, which ranged from 0.001 to 0.006 in the 1980s, has dropped to zero since 1990.
“Historically, Red Run had brook trout in the headwater section and, to my knowledge, they are no longer there,” said Mark Staley, an inland fisheries biologist with the state department.
Other Baltimore County streams studied include Baisman Run, Timber Run and Sawmill Branch.
Meanwhile, the amount of impervious land in the area, such as roads, parking lots and buildings, has grown and the amount of forested land has declined.
Brook trout require very clean, high-quality streams and prefer water temperatures of less than 60 degrees, which may explain why they are dying out or leaving Maryland.
Red Run’s average maximum daily temperature in 2005 was 73 degrees and could reach 77 degrees.
“Everything (humans) do in the watershed typically increases water temperature,” Staley said.
Stranko said the drop in their numbers is a loss for the state.
“Brook trout is our only native trout species,” he said. “It’s important to sportsmen. It’s important to people concerned with biodiversity. It’s sort of our iconic species.”
Brown trout, which is common nationwide, is now much more prevalent than brook trout in Maryland streams, he said.
“It’s the homogenization of our environment and, to me, that is very tragic because we are losing what makes these places special.”
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