Changes in Aquatic Invertebrate Community Diversity during Supra- Seasonal Drought Conditions By Briana Albini University of Hawaii at Hilo Mentor: Ayesha Burdett New Mexico Museum of Natural History and Science

Droughts Seasonal droughts ◦ Occur periodically/ seasonally Supra-seasonal droughts ◦ Random & longer than normal seasonal conditions ◦ Considered a ramp disturbance  Due to increase of disturbance over time

Drought Conditions of NM

Invertebrates Inverts evolved adaptations to seasonal drought Extreme conditions produced by supra- seasonal drought may be too much for invertebrates to handle Diptera Chironomidae Hemiptera Corixidae

Water and drought Increase in temperature, nutrient and chemical loads Decrease in D.O., surface area and volume of water body Lotic and lentic habitat ratio change Refugia can be pockets of standing water

Past Study on Invertebrates Studied differences in invertebrate composition in drinkers & springs Using data from 2010

Questions Is there a difference between the diversity levels of invertebrate communities in the springs and drinkers due to drought conditions between 2010 and 2013? Additional Questions: ◦ Can drinkers be considered refugia? ◦ Do some inverts stay dormant in dried sediments until area is wet again?

Methods Experiment was conducted on Sevilleta National Wildlife Refuge

Wet Sites Collection of aquatic invertebrates ◦ Left sponges in water sources for 10 days ◦ Took a 15x15cm quadrate sample from bottom of water source

Dry Sites Total of 3 dry sites ◦ Rio Salado ◦ Bronco ◦ Cibola Collection of sediment samples ◦ Took top soil or sediment from drinkers or springs

Methods – Lab Analysis Wet Sites Lab MethodsDry Sites Lab Methods Separate invertebrates from sediment Identify & count amount of each taxa Place sediment into clear containers & add water After 10 days, go through sample to see what emerges Identify any emergent taxa

Methods – Vegetation & Scat Survey Same methods for both surveys 4 transects going in cardinal directions Each transect is 50 m m quadrates spaced 5 m apart ◦ Surveyed for % coverage of vegetation and scat

Results Ostracoda

Results No correlation Positive correlation

Results for Dry Samples No emergent taxa found May indicate that the environment is too harsh to keep ‘seedbanks’

Results t-Test: Paired Two Sample for Means Mean Variance P(T<=t) two-tail0.818 t Critical two-tail2.446

Bronco 2010 S=3 Bronco 2013 S=0 Total Species Pool San Lorenzo E S=7 San Lorenzo E S=11 Total Species Pool Goat Draw 2010 S=1 Goat Draw 2013 S=2 Total Species Pool McKenzie 2010 S=1 McKenzie 2013 S=2 Total Species Pool Cibola 2010 S=10 Cibola 2013 S=0 Total Species Pool

Turnover Canyon 2010 S=6 Canyon 2013 S=1 Total Species Pool Gibbs 2010 S=1 Gibbs 2013 S=1 Total Species Pool Tule S=7 Tule S=3 Total Species Pool West Mesa 2010 S=3 West Mesa 2013 S=4 Total Species Pool

Discussion There is no difference in taxa richness between 2010 and 2013 Not enough springs to answer refugia question Dry springs have no invertebrate ‘seedbanks’

Improvements? More springs to compare to drinkers ◦ Need wetter conditions ◦ Couldn’t look into refugia question Switch methods ◦ Sponge removed and quadrate sample taken on same day Abundance numbers from past study

Future Study Resample wet drinkers and springs ◦ Use additional points to see how turnover changes ◦ How diversity of drinkers and springs change

Acknowledgement Thank you all very much! ◦ NSF, Sevilleta LTER Program and the US Fish & Wildlife ◦ Research Mentor: Ayesha Burdett ◦ Past Data: Amanda Martinez & Scott Collins ◦ Field Partner: Brennan Davis ◦ Sevilleta Coordinator: Amaris Swann ◦ Becky Bixby (UNM) & Bob Verb (ONU) ◦ And to everyone else who helped & supported me this summer!

QUESTIONS????

Thank You!!! Trombidiformes Hydrachnidae Hydrachna