Northern Gulf Institute
Building 1103, Room 233
Stennis Space Center, MS 39529
228.688.3099 Sharon Hodge
Gulf of Mexico Research Initiatives (GRI/BP) -- Proposal Development
Reference: June 14, 2010 Letter from Robert Dudley, BP Exploration & Production Inc.(BP Requirements Understandings) for the GRI request forimmediate research on fate and effects of oil on ecosystems (attached)
Submit to NGI Program Office in MSWord at no later than July 16, 2010
Project Lead: Linda M. Hooper-Bùi, Louisiana State University Agricultural Center, 404 Life Science Building, Baton Rouge, La 70808, 225-578-7149
Title of Proposal: Ants as bioindicators of multi-stressors on beaches and foredunes of the northern Gulf of Mexico
Period of Performance of Research:
Start: Nov 16, 2010
End: December 31, 2011
Funding Request Level:$___17,702______
Themes and Goals Addressed by Proposed Research (enter “1” for primary emphasis and “2” for all secondary emphasis areas):
NGI Themes:
1 / NGI Theme #1: Ecosystem-based management;NGI Theme #2: Geospatial data/information and visualization in environmental science;
NGI Theme #3: Climate change and climate variability effects on regional ecosystems;
2 / NGI Theme #4: Coastal hazards and resiliency
NOAA Strategic Goals:
1 / Strategic Goal #1: Protect, restore, and manage the use of coastal and ocean resources through an ecosystem approach to management;Strategic Goal #2: Understand climate variability and change to enhance society’s ability to plan and respond;
Strategic Goal #3: Serve society’s needs for weather and water information;
Strategic Goal #4: Support the Nation’s commerce with information for safe, efficient, and environmentally sound transportation;
Strategic Goal #5: Provide critical support for NOAA’s mission
Gulf of Mexico Alliance Priority Issues:
Water Quality1 / Habitat Conservation and Restoration
1 / Ecosystem Integration and Assessment
Nutrients and Nutrient Impacts
2 / Coastal Community Resilience
Environmental Education
Gulf of Mexico Research Initiative Themes:
Physical distribution, dispersion and dilution of contaminants under the action of ocean currents and tropical storms;1 / Chemical evolution and biological degradation of the oil/dispersant systems and subsequent interaction with the marine and coastal ecosystems;
1 / Environmental effects of the oil/dispersant system on the sea floor, water column, coastal waters, shallow water habitats, wetlands, and beach sediments, and the science of ecosystem recovery
Technology developments for improved mitigation, detection, characterization and remediation of oil spills;
Fundamental scientific research integrating results from the other four themes in the context of public health.
Proposal Abstract: Description of research to be conducted (limit to 500 words).
On April 20, 2010 the drilling rig Deepwater Horizon exploded and sank two days later. This opened an oil gusher in the Gulf of Mexico 41 miles southeast of the coast of Louisiana. Late in the day on April 29, 2010,the first oil made landfall at Louisiana's "bird's foot" delta and barrier marshes. Crude oil, dispersed oil, dispersants, and degraded oil in the form of poly aromatic hydrocarbons have continued to wash ashore throughout the marshes and sandy beaches of the northern Gulf of Mexico. We predict that arthropods, which are a cornerstone of the coastal food web, will be valuable indicators of the effect of these multi-stressors on the ecosystem health.This catastrophe is, therefore, an opportunity to test Petchey et al.’s (2004) conclusion that “species are lost from higher trophic levels more frequently than lower trophic levels” and also the subset model first described by Ellison et al (2002). Hooper-Bùi, in collaboration with Gene Turner and Laurie Anderson, obtained funding for an NSF Rapid proposal to investigate the effects of multi-stressors on marsh food webs in the northern Gulf of Mexico. This study is a companion study where Hooper-Bùi proposes to examine ant diversity and abundance in response to multi-stressors on sandy beaches and foredunes in the northern Gulf of Mexico. The twelve species of ants in this study have representatives at higher and lower portions of the coastal food web. Ants are easily and inexpensively sampled.
We will sample ant diversity and abundance on a large transect that extends from Texas to peninsular Florida. This transect was set up and sampled prior to oil landfall. At 13 locations along this transect, smaller transects will be sampled on the beach, the foredune and the hollow behind the foredune. We will determine diversity and abundance from ant collections using quadrat sampling and hand collecting. The ants will be identified and stored in the Louisiana State Arthropod Museum with duplicate collections in LMHB’s laboratory ant collection. A Ph.D. student, Xuan Chen, will conduct the work with the help of undergraduate student workers. All the students work closely under the direction of the PI. The PI also teaches Insect Ecology in spring at LSU and will incorporate the experiences and results of this research in her classroom teaching and field trips. Outcomes are expected to be disseminated through the primary scientific literature and through the oil spill community of practice on eXtension.org.
Methodology: Provide details and background of work to be conducted. (limit to 10 pages).
Background
The explosion and subsequent collapse of the drilling rig Deepwater Horizon presents an opportunity to look at the effects of multi-stressors on ant communities along the coast of the Northern Gulf of Mexico. While repercussions of this disaster, such as loss of vertebrate life and impact on several states’ seafood industries, are obvious to us, there is a major dearth in research over the smallest land-based organisms affected by this disaster. Soil-dwelling invertebrate species are extremely important contributors to and indicators of ecosystem health. As crude oil washes onto land, creatures such as ants are directly impacted. Because ants are intimately associated with the soil, they can serve as indicators of the presence of oil, dispersants, dispersed oil, and poly aromatic hydrocarbons (PAH)— which are termed stressors in this proposal — during oiling. Ants also are good representatives for measuring the affect of the cleanup process on the ecosystem and also the extent of the cleanup. Because of their cryptic yet immense biomass and subsequent ecological dominance, ants are one of the most important invertebrate taxa in terrestrial ecosystems (Alonso and Agosti 2000, and Hölldobler and Wilson 1990). Ants are ubiquitous and easy to collect and identify; ants can be sampled rapidly. The diversity of ants in a community is a good indicator of the diversity of other invertebrate species (Alonso 2000, Lawton et al. 1998, Majer 1983). Because of this, they are inexpensive, ideal subjects for ecological studies.
Ants are unsung aids that feed and distribute coastal plant life. They cycle nutrients into the soil and make them biologically available for plants (Lafleur et al. 2005). Harvester ants process seeds and “plant” them; the activities of these ants are often vital for plant survival. In turn, invertebrates such as ants, serve as food for vertebrates such as birds, lizards and frogs in the coastal ecosystem. Ants, which often inhabit multiple trophic levels, reside in close association to the soil and its contaminants. This allows their communities strength as sensitive indicators of ecotoxicity (Faulkner and Lochmiller 2000).
Ants are considered good indicators of biotic/habitat conditions (Andersen 1997, Blinova 2008). Ants serve as soil tillers; they have the ability to increase nutrient and mineral content in a variety of soils, particularly in wetlands (Doyle and Otte 1997). Their digging aerates soil and allows for accumulation of elements such as iron and zinc (Doyle and Otte 1997).
In coastal ecosystems, ants are often intimately associated with plants. We have found that acrobat ants (Crematogaster ashmeadi) make their nests in stems of Spartina alternaflora in marshes. Although ants nest in the soil on beaches, ants are rarely seen on the soil but rather on the plants presumably because of extreme insolation. In the coastal ecosystem associated with the northern Gulf of Mexico, ants serve not only as an indicator of soil health, but also as an indicator of plant health.
Stressors, such as those arising from hydrocarbon (HC) spills, can have dramatic, visible, and immediate direct impacts on coastal ecosystems due to the physical and toxic effects on organisms. Indirect effects also arise because, as HCs begin to degrade, toxic compounds enter food webs via primary consumers and subsequently make their way into the ant fauna.
Although there have been numerous spills that affect coastal environments, no one has examined the effects of oil, other associated pollutants, and cleanup efforts on the invertebrates that inhabit the banks and shores associated with oil spills in North America. Harrell (1985) examined the effect of oil contamination on macrobenthos in Texas. He determined that oil contamination leads to water parasites and other invasive species such as bloodworms and blind mosquitoes (Harrell 1985). Ko and Day (2004) examined the effect of Gulf oil and gas exploration and extractions on coastal ecosystems but did not mention ants. They documented that damage to microorganisms leads to potential rises in nitrates, which in turn can lead to plant die-off, nutrient imbalances, and unsafe water conditions (Ko and Day 2004). Any similar events would be detected in our study of the ants.
Furthermore, research on the effects of oil contamination of soil on ground-dwelling arthropods is sparse. Faulkner and Lochmiller (2000) surveyed abandoned oil refineries, and they conclude that the oil significantly alters arthropod species assemblages. Manaus, Amazonas, Brazil has a history of oil and sewage issues; Cururu and Bom Jardim streams have suffered heavy impact (Couceiro et al 2007). Affected streams and associated land areas had lower invertebrate abundance and fewer edaphic (soil dwelling) invertebrate communities (Couceiro et al 2007). Ants and other arthropods that cannot escape oil pollution have strong likelihood of asphyxiation (Ambethgar 2009). Recolonization of existing species may be delayed (Decker and Fleeger 1984).
In the past eight months we have collected more than 12 species of ants in the coastal areas of Louisiana, Mississippi, Alabama and Florida (Table 1). These species represent different portions of the food web. Crematogaster or acrobat ants have a plant-based diet (honeydew, nectar, plant sap) that is supplemented by meats. Dorymyrmex, or the pyramid ants, are solely predacious, particularly on other ants. Another predacious ant is Cardiocondyla, which will cut up larger insects before bringing them back to the nest (Wilson 1959). Both Forelius (cheese ants) and the invasive Solenopsis invicta (fire ants) are catholic in their tastes as they will eat just about anything and are representatives of species high in the coastal food web. Pogonomyrmex, the harvester ants, have a diet that is dominated by the seeds of nearby plants; they will supplement their diet with insects.Pogonomyrmex and Crematogaster represent species that are lower in the food web.
Table 1. Preliminary list of ant species from coastal northern Gulf of Mexico.
Ants / Louisiana / Mississippi / Alabama / FloridaCrematogaster ashmeadi / X / X / X / X
Dorymyrmex sp 1 / X / X / X / X
Dorymyrmex sp 2 / X / X
Brachymyrmex patagonicus / X / X / X / X
Brachymymex depilis / X / X
Cardiocondyla nr. sp. nuda / X / X
Pogonomyrmex badius / X / X
Solenopsis invicta / X / X / X / X
Forelius sp 1 / X / X / X / X
Forelius sp 2 / X / X
Forelius sp 3 / X / X
Forelius sp 4 / X / X
Both Solenopsis and Pogonomyrmex are predicted to be the most sensitive ants to multi-stressors. Fire ants extensively excavate the soil, and they would be the ant species that would have the most exposure to toxins in the soil. Their huge colonies would be impacted by the reduction in available food sources. Because of their invasive, resilient habits, fire ants are also likely to be the species most likely to re-infest the area. The harvester ants, on the other hand, are susceptible to environmental toxins and are least likely to rebound. Markin et al. (1974a) conducted a study of the fire ant bait (insecticide) Mirex on Cat Island south of Gulfport and found that three years after the final application, the ant had been eradicated and no new colonies had been discovered on the island. Interestingly, five other species of ants, Conomyrma insana (Buckley) (which is now Dorymyrmex), Iridomyrmex pruinosus (Roger) (which is now Forelius), Crematogaster clara (Mayr), and two species of Camponotus, appeared not to have been affected immediately after and three years after treatment (Markin et al. 1974a). Markin et al. (1974b) also reported the total extirpations of Pogonomyrmex badius from Washington Parish in eastern Louisiana due to Mirex applications for fire ants. Starting in 1999, LMHB searched for these ants and rediscovered the harvester ants in the area in 2008 more than 30 years after they were reported extirpated (Dash and Hooper-Bùi 2008). This leads to our hypothesis that Dorymyrmex, Forelius, and Crematogaster are likely to be less affected by multi-stressors than Solenopsis and Pogonomyrmex.
Hypotheses:
•Dorymyrmex, Forelius, and Crematogaster are likely to be less affected by multi-
stressors than Solenopsis and Pogonomyrmex;
•Ants inhabiting beaches and foredunes will be a subset of the generalist ants found in
surrounding marshes and forests (Ellison et al 2002);
•Species turnover is an accurate indicator of long-term health of the plant community
that precedes obvious changes in the above- and belowground biomass. We predict
species turnover will be greater as stressors increase;
•Stressor effect on species turnover will be strongly associated with trophic level and
specific life history traits of the ants, particularly level of soil excavation.
•Invasive species that specialize in disturbed areas will increase
Research Methods
This study will be undertaken in state parks and/or uninhabited coastal areas along the northern Gulf of Mexico because these places suffer fewer disturbances. Last fall, we began an intensive study of ants in coastal areas in preparations for our continued work on the effects of hurricanes and storm surge on ant fauna. In May,we established a coastal transect from Texas to peninsular Florida prior to oil landfall. Subsequent sampling will measure the changes in ant diversity and abundance. At each location, we will place a 40 meter transect on the beach, one parallel transect on the foredune, and another parallel transect the hollow behind foredune. Ants will be collected along all transects using two methods: quadrat sampling and hand collecting.
Quadrat sampling. Five to 10 metal quadrats (60cm x 60cm) will be located on each transect at 10 meters intervals. Since the ants are associated with the plants on the beach, the nearest plant to the point on the transect will serve as the center of the quadrat. The quadrat is made of metal flashing 26cm in width formed into a square. The sides of the quadrat will be coated with Teflon which prevents the ants from climbing out and escaping. The quadrat will be pressed into the sand and all the ants inside are quickly collected by aspirator and then transferred to bottles with 95% ethanol. Temperature, humidity, vegetation cover, plant height will be measured at each quadrat. Representative plants will be collected, pressed, and identified to determine plant species composition.
Hand collecting. Direct sampling will consist of a visual search and capture of ants foraging on the ground or plants for about half an hour in and around each transect after quadrat sampling. Ants will be collected by aspirator or forceps and stored in bottles with 95% ethanol.
Identification. Ants are identified to genus using Bolton (1994). All ants in the study will be indentified to species using the appropriate keys from the literature. LMHB and the Louisiana State Arthropod Museum have an extensive reference ant collection to which specimens can be compared. Specimens that are unique will be verified by taxonomy specialists.
We expect this project to generate data that will be leveraged for additional multi-year funding. This is a long-term project.
References
Alonso, L.E. 2000. Ants as indicators of diversity. Pp. 80—88, In D. Agosti, J.D. Majer, L.E. Alonso, and T.R. Schultz (Eds.). Ants: Standard Methods for Measuring and Monitoring Biodiversity. Smithsonian Institution Press, Washington, DC. 248 pp.
Alonso, L.E., and Agosti, D. 2000. Biodiversity studies, monitoring, and ants: an overview. Pp. 1—8, In D. Agosti, J.D. Majer, L.E. Alonso, and T.R. Schultz (Eds.). Ants: Standard Methods for Measuring and Monitoring Biodiversity. Smithsonian Institution Press, Washington, DC. 248 pp.
Ambethgar, V. 2009. Potential of entomopathogenic fungi in insecticide resistance management (IRM): a review. J. Biopest. 2(2): 177-193.
Andersen, A.N. 1997. Using ants as bioindicators: Multiscale issues in ant community ecology. Conservation Ecology 1: 8.
Blinova, S.V. 2008. Changes in ant assemblages under conditions of a large industrial center. Russian J. Ecology 39(2): 148-150.
Bolton, B. 1994. Identification Guide to the Ant Genera of the World. Harvard University Press. Harvard College, Cambridge, Massachusetts.
Couceiro, S.R.M., Hamada, N., Ferreira, R.L.M., Forsberg, B.R., and da Silva, J.O. 2007. Domestic sewage and oil spills in streams: effects on edaphic invertebrates in flooded forest, Manaus, Amazonas, Brazil. Water Air Soil Pollut. 180: 249-259.
Dash, S.T and L.M. Hooper-Bùi . (2008) Species diversity of ants (Hymenoptera: Formicidae) in Louisiana. Annals of the Entomological Society of America101:6, 1056-1066
Decker, C.J. and Fleeger, J.W. 1984. The effect of crude oil on the colonization of meiofauna into salt marsh sediments. Hydrobiologia 118: 49-58.
Dyle, M.O. and Otte, M.L. 1997. Organism-induced accumulation of iron, zinc, and arsenic in wetland soils. Environ. Pollut. 96: 1-11.
Ellison, A.M., Farnsworth, E.J., & Gotelli, N.J. 2002. Ant diversity in pitcher-plant bogs of Massachusetts. Northeast Nat. 9: 267-284.
Faulkner, B.C., and Lochmiller, R.L. 2000. Increased abundance of terrestrial isopod populations in terrestrial ecosystems contaminated with petrochemical wastes. Arch. Environ. Contam. Toxicol. 39: 86–90.
Harrell, R.C. 1985. Effects of a crude oil spill on water quality and macrobenthos of a southeast Texas stream. Hydrobiologia 124: 223-228.