Archbold Biological Station
Biennial Report 1995-1996
P.O. Box 2057 Lake Placid, Florida 33862 USA
Phone: 863-465-2571 FAX: 863-699-1927
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Representative Visiting Scientists including: Curtis S. Adkisson, Virginia Polytechnic Institute (VPI); James E. Carrel, University of Missouri-Columbia; William E. Conner, Wake Forest University; Jack P. Hailman, University of Wisconsin; Margaret A. Hodge, College of Wooster; Sam D. Marshall, Miami University; Ronald L. Mumme, Allegheny College; William A. Watts, Trinity College, Dublin
Visiting scientists have made important contributions to the Station's scientific productivity since its founding. The tradition continues in 199596 with vigor and excellence. We profile eight visiting scientists including four long-term visitors and four relative newcomers that are establishing long-term studies.
Curtis Adkisson began a research leave from VPI in August 1996, studying the role played by blue jays in the recolonization of oaks in severely disturbed sites, such as citrus groves. Blue jays harvest acorns from late August until November, with more than 500 flights per day by birds carrying acorns in their throats from the Station's Red Hill to the groves south of Archbold Road. These nuts are hidden individually in the sand beneath or between orange trees. Many germinate in some years (such as the spring of 1994), and have the potential to replace the orange trees if these should die, as has happened in places where freezes killed the groves. Radio-transmitters placed on the jays will help estimate the number of acorns taken to these groves, and the potential for recovery of scrub oaks on the Lake Wales Ridge.
James Carrel currently works on two projects at the Station. One is a study of the ecology of blister beetles, particularly their use of the toxin cantharidin for defense against predation. In collaboration with Thomas Eisner (Station Research Associate) and others he has staged encounters between the large blister beetle, Lytta polita, and a variety of predators. He also used this beetle species to study the biosynthetic pathway for cantharidin. The second, begun in 1987, is on the population ecology of four scrub-endemic spiders. He is studying spider densities in different habitats and performing tests to determine factors that affect spider populations in scrub. Finally, in collaboration with his wife, Janet Weaver, Carrel is initiating an inventory of the arachnids at the Station. In the coming years they hope to collect and identify most of the spider species and to acquire much information about their life histories.
Bill Conner studies the association of adult arctiid moths and pyrrolizidine alkaloids (PAs). Early in the 20th Century in South America, William Beebe found that the dead shoots of Heliotropium indicu, a PA-containing plant, attracted butterflies and moths. In some arctiid moths PA-visitation is male-biased (eg. in Cosmosoma myrodora), in some female-biased (eg. in Halysidota tessellaris), and in others both sexes visit PA-sources (eg. in Eucereon carolina). In collaboration with Thomas Eisner (Station Research Associate), Conner hopes to discover the functions of PA-visitation. Do PAs collected by adult arctiids; a) provide a defense against predators, b) affect their male pheromone content and courtship behavior, or c) influence spermatophore weight for males and egg production for females? Conner recently (fall 1996) replicated the experiments of Beebe using dog fennel (Eupatorium capillifolium) as bait and determined that it is feasible to study the phenomenon at the Station.
Jack Hailman told us he was dumbfounded to discover in the American Heritage Dictionary the headword "ethogram." Perhaps the entry symbolizes a coming of age for ethology, the study of animal behavior. "We have aged together, ethology and ethologist, as I have worked toward compiling for the Florida scrub-jay a 'catalog' of the behavioral patterns of an organism or a species," Hailman writes. At the invitation of Glen Woolfenden, Hailman began studying Aphelocoma coerulescens in 1980. His coauthors A. Margaret Elowson, Anne Marie Francis, Kevin J. McGowan, and Woolfenden subsequently published with him journal papers on nest defense, mobbing, alarm calls, jay-dove interactions, and sentinel behavior. Hailman's current graduate students Peter E. Midford and Douglas A. Kramer are finishing thesis research on foraging traditions and acorn caching, respectively. Hailman is spending academic year 1996-97 on sabbatical at the Station, assembling years of observations into a monographic treatment of scrub-jay behavior and filling in gaps with new field research. Locomotion, preening, foraging, anti-predator behavior, tameness, dominance, courtship, nest-building, incubation, caring for youngthese and many other topics compose the ethogram.
Margaret Hodges research concerns interactions between two species of nocturnal wolf spiders of scrub habitats. Both (Lycosa osceola and L. ceratiola) are the predominant terrestrial spiders in scrub. Surveys of habitat use by these two species show that the larger osceola occurs on leaf litter while the smaller ceratiola occurs on bare sand. Pitfalls and sticky traps find significantly more insect prey on leaf litter than on bare sand. Presented with a choice of substrates in field enclosures, osceola prefers to hunt on leaf litter and ceratiola has an equal preference for either leaf litter or bare sand. However, in the presence of osceola, ceratiola switches to exclusive use of bare sand which is poor in prey. This suggests that interference competition may drive habitat segregation between these spiders. Additionally, 20% of the diet of osceola consists of ceratiola individuals. Therefore, habitat use by ceratiola may represent a tradeoff between foraging success and avoidance of competition and predation.
Sam Marshall is collaborating with Station Research Biologist Mark Deyrup (see page 14) on a biogeographic study of the burrowing wolf spiders (Geolycosa) endemic to Florida. This North American genus reaches its peak of diversity in Florida's xeric uplands and is uniquely adapted to life in sand. Results indicate the present distribution patterns are correlated with the historical biogeography of Florida scrubs and sandhills. This research was begun while Marshall was a graduate intern at the Station in 1993 and will soon be ready for submission. Marshall also collaborates with his wife, Maggie Hodge, in her studies of community ecology of scrub wolf spiders.
Ronald Mumme, visiting Archbold since 1986, has continued his long-term research on the behavioral ecology and conservation biology of the Florida scrub-jay. He has primary responsibility for color-banding, censusing, and maintaining records of the scrub-jay population in the "experimental tract"portions of the Station south of the main scrub-jay study area (the "demography tract"). During 1995-96, Mumme's research focused on two conservation-related issues: 1) demographic consequences of roadside mortality, and 2) viability of translocation as a management technique. The latter research, in collaboration with Theodore H. Below (National Audubon Soc.), began in 1989 and is funded by the Florida Nongame Wildlife Program. Mumme also continues to collaborate with Stephan J. Schoech (Univ. of Indiana). Schoech's dissertation research on the behavioral endocrinology of Florida scrub-jays was conducted at Archbold during 1992-94 and made extensive use of the experimental tract population.
William Watts. During 1995-96 a team led by George and Heather Jacobson (Univ. of Maine), Eric Grimm (Illinois State Mus.) and Bill Watts, studied the climatic and environmental information recorded by Lake Annie's sediments. A core of lake-mud extracted from the lake's deepest part (20 m of water, marked by a permanent buoy) was 18 m and longer than previous cores. Radiocarbon dates (n=14) place this core's base at about 11,700 years old. The lake was very shallow then; probably a small pond based on the frequent macrofossils of Pistia stratiotes and Ceratophyllum sp., aquatics absent in Lake Annie today, but widespread in Florida. Just before 10,000 years ago, the lake seems to have dried up completely. Pollen of Chenopodiaceae is abundant, evidence of a weed-colonised, dried-up surface. More drilling is required; the team thought it had reached bottom, but there must be more sediment below, perhaps concealed by thin sand beds.
Lohrer, F.E . (Editor). 1998. Archbold Biological
Station, Biennial Report 1995-1996. Archbold Biological Station, Lake Placid. 62 pp.
© Archbold Biological Station, 1998, October.
Webmaster: Fred Lohrer.