Download GCPLCC_F_E_Hypotheses_examples_and_format_101912

GCPLCC Instream Flow Project
DRAFT Regional Flow-Ecology
Hypotheses:
Examples and Format
October 19, 2012
Categories of Flow-Ecology Hypotheses
• Biotic Interactions
– Species
– Guild
– Community
• Physical Habitat
- Availability
• Water quality
– DO
– Temperature
• Energy Supply
- OM Transport
GCPLCC Regional Flow-Ecology Hypotheses
Subsistence Flows
Ecoregion: Coastal
River Class: small, low gradient, warm streams and rivers
Subsistence Flow Hypothesis #1: Dissolved oxygen and temperature are adversely affected by reduced magnitude
of subsistence flows
Effected species: All fish, mussels, and other riverine species sensitive to and unable to avoid low oxygen and high
temperatures
Water Quality Parameter
+
0
Dissolved Oxygen
Temperature
-
0
Altered subsistence flow – magnitude
+
Source: Sabine-Neches BBEST Biological Overlay Appendix XIII
Alternate Graphical F-EH Format
GCPLCC Regional Flow-Ecology Hypotheses
Subsistence Flows
Ecoregion: Coastal
River Class: small, low gradient, warm streams and rivers
Subsistence Flow Hypothesis #1: Dissolved oxygen and temperature are adversely affected by reduced magnitude
of subsistence flows
Altered Water Quality Parameter
Effected species: All fish, mussels, and other riverine species sensitive to and unable to avoid low oxygen and high
temperatures
0
Dissolved Oxygen
Temperature
-
0
Altered subsistence flow – magnitude
+
Source: Sabine-Neches BBEST Biological Overlay Appendix XIII
GCPLCC Regional Flow-Ecology Hypotheses
Subsistence Flows
Ecoregion: All
River Class: headwaters, streams, and small rivers
Subsistence Flow Hypothesis #2: Extended periods of subsistence flows strands fish in pools and other isolated
bodies of water (e.g., oxbows) where they become concentrated and predation increases.
Effected species: Channel and blue catfish, small mouth buffalo, gar , and other large and small fish
Abundance
+
0
Predatory species
Prey
-
0
Altered subsistence flow – duration
+
Source: Sabine-Neches BBEST Biological Overlay Appendix XIII
GCPLCC Regional Flow-Ecology Hypotheses
Base Flows
Ecoregion: All
River Class: All
Base Flow Hypothesis #1: Sediments become more stable during periods of extended base flow, which is beneficial
for many mussel species. (Vaughn and Taylor 1999, Strayer 2008)
Base Flow Hypothesis #2: Mussels feed on higher densities of water-column food resources during periods of
extended base flow (Rypel et al. 2009)
Effected species: All mussel species (e.g., Quadrula fragosa (Winged mapleleaf), Leptodea leptodon (Scaleshell)
# of mussel species
+
0
-
0
Altered base flow – duration
+
Source: Sabine-Neches BBEST Biological Overlay Appendix XIII
GCPLCC Regional Flow-Ecology Hypotheses
Base Flows
Ecoregion: All
River Class: headwaters, streams, and small rivers
Base Flow Hypothesis #3: Sight-oriented predatory fish can exploit prey populations that are at high densities and in
clear water during extended periods of base flows, especially during summer and fall.
Effected species: Sight-oriented predatory fish and their prey
Abundance
+
0
Predatory fish species
Prey
-
0
Altered base flow – duration
+
Source: Sabine-Neches BBEST Biological Overlay Appendix XIII
GCPLCC Regional Flow-Ecology Hypotheses
Base Flows
Ecoregion:
River Class: headwater, streams, and small rivers, moderate gradient
Base Flow Hypothesis #4: Reduced base flow exposes riffles reducing the extent of available habitat and the
abundance of riffle-obligate species.
Abundance of riffle-obligate species
Effected species: All riffle-obligate species (e.g., Etheostoma spectabile (Orangethroat darter))
+
0
-
0
Altered base flow – magnitude
+
Source: TNC-OK
GCPLCC Regional Flow-Ecology Hypotheses
High Flow Pulses
Ecoregion:
River Class:
High Flow Pulse Hypothesis #1:.
Effected species:
Parameter
+
0
Parameter #1
Parameter #2
-
0
Altered High Flow Pulses– duration
Source:
+
GCPLCC Regional Flow-Ecology Hypotheses
Overbanking Flows
Ecoregion:
River Class:
Overbanking Flow Hypothesis #1:.
Effected species:
Parameter
+
0
Parameter #1
Parameter #2
-
0
Altered Overbanking Flow– duration
Source:
+