Amphibian population estimates and ecosystem assessment on the Durango Nature Studies property
Durango Nature Studies (DNS) is an area of land that is used by students of all ages to go out and learn about the area and habitat around them. A variety of local organizations use this property for biology-based research; Fort Lewis College, Animas High School, and Southwest Conservation Corps. Durango Nature Studies is located at the bottom of Bondad Hill, the area around there is very dry except for the river and pond that are located there. The habitats on the DNS property include the pond, river and the forest. In recent years, bullfrogs have been spotted on the DNS property.
The status of the bullfrogs in Colorado is invasive. This means they have the ability to out-compete the other frog species for resources. The main species that is being affected in Colorado is the leopard frogs. The bluegill is another non-native species that has been stocked in the DNS pond for children’s fishing programs. These two non-native species are harmful to the environment because the bullfrogs push the leopard frogs back into open area for the blue gill to attack them. The status of the leopard frogs currently in Colorado is a state species of special concern.
Methods & Materials
Some of the strategic methods that were used to catch the leopard frogs and bullfrogs were to set pit traps, this worked by digging a hole in the ground and then making only one entrance to the hole so that the frog would wander around until it fell inside the hole. then a visual encounter was enabled around the pond each day for 4 days. Afterwards a one hour mark session was put in place and then soon after a one hour recapture session took place. Then water chemistry tests were conducted for nitrates, phosphates, dissolved oxygen, and finally pH. Then macroinvertebrates were collected from the river using certain methods such as the kick method and shuffle method, with this method certain macroinvertebrates were captured such as the mayfly, damselfly, midge, caddisfly, dragonfly, stonefly, and the cleopatra. Afterwards in the pond the net was used to capture the macroinvertebrates, the species that were collected are similar to the ones in the river.
Results
From resent research the nitrate levels for every part per million (ppm) in the pond is 6, the river is 10, and while the normal level is 4 the dangerous level is 40. The phosphate levels in the pond and river is 4 ppm and normal levels is .03. then the pH in the pond is 8 while in the river it is 10 ppm and the neutral water levels was 7. Then the dissolved oxygen level for the pond is 1 ppm and the river and normal levels are both 3 ppm. And the coliform in the pond and the river are both positive.
Last year there were 102 macroinvertebretes found in the pond so the biodiversity was .99, but this year in 2012 there were only 20 macroinvertebretes found in the pond and the biodiversity was 1.21, this shows that the bugs are being affected someway. Then in the river last year there were 270 macroinvertebretes found meaning that the biodiversity was 1.03, then in the river the amount of bugs that were found was 364 this year which meant that the biodiversity index was .88.
Conclusion
All of the data that has been collected tells us that the macroinvertabretes are being affected in away because the amount of macroinvertebretes are decreasing in the ponds, this is most likely because of pollution. This is said because the insects are highly intolerant with the pollution and are affected immediately so if the amount of macroinvertebretes starts to decrease then that means they are being killed by pollution. The population of amphibians is lowering for some species such as the leopard frog while the invasive bullfrog is increasing largely. Also the water quality is in bad condition because in the graph it shows that there is lots of dangerous levels in the water, an example of dangerous levels is the level of nitrates in the water. Reasons for the dangerous levels is pollution and other wastes that are being dumped or buried into the ground because all of those lead to a water source. Ways to get data much better would to find really specific areas and then create a perimeter around a certain part of the river and make sure it is at the same time every year. A way that the pond can be better managed for leopard frogs is to wipe out the invasive species and put the normal food chain back in line.
Durango Nature Studies (DNS) is an area of land that is used by students of all ages to go out and learn about the area and habitat around them. A variety of local organizations use this property for biology-based research; Fort Lewis College, Animas High School, and Southwest Conservation Corps. Durango Nature Studies is located at the bottom of Bondad Hill, the area around there is very dry except for the river and pond that are located there. The habitats on the DNS property include the pond, river and the forest. In recent years, bullfrogs have been spotted on the DNS property.
The status of the bullfrogs in Colorado is invasive. This means they have the ability to out-compete the other frog species for resources. The main species that is being affected in Colorado is the leopard frogs. The bluegill is another non-native species that has been stocked in the DNS pond for children’s fishing programs. These two non-native species are harmful to the environment because the bullfrogs push the leopard frogs back into open area for the blue gill to attack them. The status of the leopard frogs currently in Colorado is a state species of special concern.
Methods & Materials
Some of the strategic methods that were used to catch the leopard frogs and bullfrogs were to set pit traps, this worked by digging a hole in the ground and then making only one entrance to the hole so that the frog would wander around until it fell inside the hole. then a visual encounter was enabled around the pond each day for 4 days. Afterwards a one hour mark session was put in place and then soon after a one hour recapture session took place. Then water chemistry tests were conducted for nitrates, phosphates, dissolved oxygen, and finally pH. Then macroinvertebrates were collected from the river using certain methods such as the kick method and shuffle method, with this method certain macroinvertebrates were captured such as the mayfly, damselfly, midge, caddisfly, dragonfly, stonefly, and the cleopatra. Afterwards in the pond the net was used to capture the macroinvertebrates, the species that were collected are similar to the ones in the river.
Results
From resent research the nitrate levels for every part per million (ppm) in the pond is 6, the river is 10, and while the normal level is 4 the dangerous level is 40. The phosphate levels in the pond and river is 4 ppm and normal levels is .03. then the pH in the pond is 8 while in the river it is 10 ppm and the neutral water levels was 7. Then the dissolved oxygen level for the pond is 1 ppm and the river and normal levels are both 3 ppm. And the coliform in the pond and the river are both positive.
Last year there were 102 macroinvertebretes found in the pond so the biodiversity was .99, but this year in 2012 there were only 20 macroinvertebretes found in the pond and the biodiversity was 1.21, this shows that the bugs are being affected someway. Then in the river last year there were 270 macroinvertebretes found meaning that the biodiversity was 1.03, then in the river the amount of bugs that were found was 364 this year which meant that the biodiversity index was .88.
Conclusion
All of the data that has been collected tells us that the macroinvertabretes are being affected in away because the amount of macroinvertebretes are decreasing in the ponds, this is most likely because of pollution. This is said because the insects are highly intolerant with the pollution and are affected immediately so if the amount of macroinvertebretes starts to decrease then that means they are being killed by pollution. The population of amphibians is lowering for some species such as the leopard frog while the invasive bullfrog is increasing largely. Also the water quality is in bad condition because in the graph it shows that there is lots of dangerous levels in the water, an example of dangerous levels is the level of nitrates in the water. Reasons for the dangerous levels is pollution and other wastes that are being dumped or buried into the ground because all of those lead to a water source. Ways to get data much better would to find really specific areas and then create a perimeter around a certain part of the river and make sure it is at the same time every year. A way that the pond can be better managed for leopard frogs is to wipe out the invasive species and put the normal food chain back in line.