Author: Bill Buchanan. PoTs and IP Network Author: Bill Buchanan Base rate.
Grace Gardner, Joe Buchanan, Casey Kristofferson
description
Transcript of Grace Gardner, Joe Buchanan, Casey Kristofferson
Grace Gardner, Joe Buchanan,Casey Kristofferson
Pond Zooplankton Analysis at OX Ranch
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
X
X
X
X
X
X
Black X: Offshore sitesGray X: Onshore sites
Volume of offshore= 14015 m^3Volume of onshore =1300 m^3
Onshore vs. Offshore
vesr.ucnrs.org
wildco.com
Sampling
Reasoning: Daphnia
• Pond Community • Role of Daphnia
Trophic Level 4 Human
Trophic Level 3 Planktivore
Trophic Level 2 Zooplankton Daphnia
Trophic Level 1 Phytoplankton
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
Daphnia Ceriodaphnia Alona Cyclopoid Chaoborus Odonata0
0.2
0.4
0.6
0.8
1
1.2
Zooplankton Abundance; Onshore vs Offshore
Onshore Offshore
Genera
Abun
dace
#/L
10
0.5
1
1.5
2
2.5
3
Length of Zooplankton; Offshore vs. Onshore
OffshoreOnshore
Pond Zone
Aver
age
Lent
h (m
m)
11
1.05
1.1
1.15
1.2
1.25
1.3
Daphnia Length: Offshore vs. Onshore
Offshore Onshore
Pond Zone
Leng
th (m
m)
10
1
2
3
4
5
6
7
8
9
Daphnia Biomass (mg/L) of Onshore vs. Offshore
OffshoreOnshore
Pond Zone
Biom
ass (
mg/
L)
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)
(Burns 1968)
Parameters Pond Total
Daphnia Biomass (mg/L) 11.77776678
Daphnia Abundance (#/L) 1.405452
Daphnia Average Length (mm) 1.193735
Zooplankton Length (mm) 1.86216
Daphnia length range: 0.30928- 2.7062mm
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.
Daphnia Ceriodaphnia Alona Cyclopoids Chaoborus Odantata0
0.5
1
1.5
2
2.5
Zooplankton Abundance; Night vs. Day Offshore
NightDay
Species
Abun
danc
e (#
/L)