South Texas Ecology Lab
Does Size Matter: Juvenile Fish recruitment using Cement Blocks
Low-profile artificial reefs may be beneficial to supplement fisheries by providing simple hard-bottom substrate for reef fish species at various life stages. In this study, we set out to determine the optimal size patch reef to recruit juvenile red snapper (Lutjanus campechanus). Cinder blocks were arranged in eight arrays with replicates of: single block, 2 blocks, 4 blocks, and 16 blocks away from any hard substrate. Arrays will be monitored for one year and reef fish abundance and size classes at each replicate recorded. Preliminary surveys have revealed juvenile red snapper at several patch sizes. This suggests that deployment of low-profile structures near existing artificial reefs may be an effective tool to increase juvenile recruitment.
Red Snapper Accelerometer Telemetry
Utilizing Accelerometer Telemetry Tags to Compare Red Snapper (Lutjanus campechanus) Movements on Natural and Artificial Reefs.
Artificial reefs are used throughout the Gulf of Mexico to enhance fish stocks and fisheries. Fishes such as red snapper are clearly drawn to these structures, but it is not certain how well they mimic natural reefs. My research involves assessing movements of red snapper on oil platforms, ships and natural reefs to determine habitat preference and estimate energy budgets on each reef type. To meet this goal, I am utilizing accelerometer telemetry tags to determine overall dynamic body acceleration and categorize behaviors such as hovering and prey capture attempts in wild fish.
Population Genetics of the Black Spotted Newt
The black-spotted newt (Notophthalmus meridionalis) is an endangered amphibian in south Texas and coastal Mexico. Since its discovery agriculture, urbanization, species introduction, and pesticide use has gradually degraded potential habitat for this species.
My study focuses on identifying contemporary populations and conducting genetic analysis to identify variation within populations. Using environmental DNA, I will be able to effeciently identify newt inhabited locations. Once newts are found, tissue samples are collected for genetic analysis using ddRAD sequencing. In the future this work can help reintroduction efforts.
Are there Ocelots about?
We are studying the last two surviving endangered ocelot populations found only here in South Texas by using motion sensor cameras as a noninvasive alternative to physically trapping and handling the felids. The camera photos collected will then be used for statistical analysis of ocelot and bobcat density estimates. These density estimates should give great insight into the level of competition between these two carnivores. I hypothesize that the excessive abundance of generalist bobcats are hindering any recovery of the specialist ocelots.