Students Briefs

Anabella Zuluaga

Doctoral candidate Anabella Zuluaga is investigating the spatial variation of the fungal community of sea fans in six reefs in Puerto Rico. As part of her investigation, she monitors the sea fans three times at year to determine incidence and prevalence of aspergillosis, a sea fan disease. She has found that detachment from the ocean floor is a more common cause of death in sea fans than aspergillosis. She also has found that the disease is increasing only in Jobos Bay and hypothesizes that this may be caused by warm water discharge from a thermoelectric plant. Otherwise, she found that the mycoflora in sea fans vary spatially, which suggests that the composition of fungal community is influenced by local environmental factors such as coastal currents, sea temperature, or river and sewage discharge—not by Saharan dust, as was previously believed. Zuluaga’s results may aid in drafting local environmental protection laws.

Paola Olaya

A master’s student in biology, Paolo Olaya is studying the effects of climate change on a tiny orchid endemic to Puerto Rico, Lepanthes rupestris. Olaya is overlaying previously collected demographic data with temperature and precipitation data for the same nine-year time period. She is investigating whether temperature and precipitation have changed during this time, and if so, what effect it has had on Lepanthes community dynamics. Olaya has several hypotheses that she will test, for example, that temperature regulates fruit production. In general, flowers are produced in a rainy period and fruits appear in a dry period. If a dry or wet spell were extended—a predicted consequence of climate change—what effect would it have on the orchids? Olaya predicts that this would negatively affect Lepanthes orchid populations.

Charito Orengo

Biology master’s student Charito Orengo’s research will involve the collection of baseline data about a non-native ant that invaded Puerto Rico about 40 years ago. Since then the population of Solenopsis invicta—commonly known as the red fire ant—has grown, sparking concerns about its effects on arthropod diversity and agriculture. To study the foraging behavior of the polygyne (multiple queen) fire ants, Orengo removes foragers from baited traps and anesthetizes them in the field in order to mark them with florescent spray paint. Then she returns the marked ants near the nest and the next day places baited ant traps at different distances. With the recaptured ants, she can map their foraging areas and determine the distance they travel for food. Orengo’s research about the foraging behavior of these ants may contribute to their control on a small scale, for example, in urban areas.