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Pond Zooplankton Analysis at OX Ranch. Grace Gardner, Joe Buchanan, Casey Kristofferson . Outline. Background Methods Data Results Management Summary. Background. Purpose of ponds Macrophytes Location- middle pond Zooplankton Assessment October 7 th and 8th. Methods.
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Pond Zooplankton Analysis at OX Ranch Grace Gardner, Joe Buchanan, Casey Kristofferson
Outline • Background • Methods • Data • Results • Management • Summary
Background • Purpose of ponds • Macrophytes • Location- middle pond • Zooplankton Assessment • October 7th and 8th
Methods • Onshore vs. Offshore • Equipment • Sampling • Lab Analysis • Reasoning
Onshore vs. Offshore X Volume of offshore= 14015 m^3 Volume of onshore =1300 m^3 X X X Black X: Offshore sites Gray X: Onshore sites X X
Sampling wildco.com vesr.ucnrs.org
Reasoning: Daphnia • Pond Community • Role of Daphnia
Data and Results • Comparisons of Offshore and Onshore zones • Abundances of all Zooplankton genera present • Average length of zooplankton • Average length of Daphnia specifically • Average biomass of Daphnia • If time permits: abundances between night and day within the offshore zone
Large-bodied Daphnia benefits • Burns et al. 1968, found a correlation between length of zooplankton and diameter of particle able to filter • This means that the larger-bodied zooplankton within onshore zone are providing top-down control upon algal blooms • Management implications with removal of these zooplankton (Burns 1968)
Management • Ox Ranch Plan • Suggestions • Role of management plan
Pond Status • Pond is in great condition for Daphnia. • High densities of Macrophytes • Good for daphnia • Bad for fish
Management Suggestion • Macrophyte removal • Dredging • Fish habitat • Fish stocking • Shading • Role
Macrophyte Removal • Remove 30-40% of macrophytes • Mostly near/around dock • Significance
Dredging • 3 meters deep • In front of dock • Depth for fish habitat
Fish habitat • Brush piles in open water • In dredging area • Christmas trees, brush, anything. • (Bassett et al. 1994)
Stocking • Conservative • Fish population boom at beginning • Ecosystem reaction
Shading • Plant willows • Shading of pond • Bank stabilization
Role of Management plan • Economically effective • Maintain balance • Supply fishing opportunities
Summary • Background • Methods • Data • Results • Management • Questions?
Citations • Bassett, C. E. 1994. Use and evaluation of fish habitat structures in lakes of the eastern United States by the USDA Forest Service. Bulletin of Marine Science, 55: 1137-1148. http://idahoid.library.ingentaconnect.com/content/umrsmas/bullmar/1994/00000055/F0020002/art00070 • Burks, R.L., Jeppersen, E., and Lodge, D.M. 2001. Littoral zone structure as Daphnia refugia against fish predators. Limnology and Oceanography 46: 230-237. • Burns, C.W. 1968. The relationship between body size of filter-feeding cladocera and the maximum size of particle ingested. Limnology and Oceanography 13: 675-678. • Wetzel, R.G. 2001. Limnology. 3rd Ed. Academic Press, San Diego, CA, U.S.A.