Invasive species have large economic and ecological impacts and are the leading driver of extinction for both plants and animals worldwide. In the USA, coral reefs, which provide $3.4 billion per year in ecosystem services, are impacted by invasive marine species. One such species is Tubastraea coccinea, which was the first scleractinia to invade the western Atlantic and recently has spread to natural reefs within the northern Gulf of Mexico (GoM). We document this recent invasion by compiling occurrence records, develop a species distribution model identifying important determinants of invasion, and project potential range expansion. Our results indicate T. coccinea currently is distributed along the GoM coast from the Florida Keys to southern Texas, with documented localities clustered ≈ 100 km off the Louisiana coast and ≈ 200 km off the Texas coast, and sparsely distributed elsewhere. Our species distribution model identified five environmental factors that together contribute > 99% to the overall model. These factors include two surface variables (mean pH and mean calcite, contributing ≈ 40%) and three benthic variables (maximum current velocity, minimum iron, and minimum dissolved oxygen, contributing ≈ 60%). Our model suggests potential habitat for range expansion is distributed mainly within the western portion of the northern GoM, with the highest probabilities of occurrence (0.8 < P < 1.0) clustered along the Texas and Louisiana coasts between 88 and 97°W (near the border between states).

One of the major drivers of amphibian population declines is Batrachochytrium dendrobatidis (Bd). We sought to identify the major environmental drivers of Bd prevalence in Texas, USA, by drawing results from museum specimens. We sampled one of the largest museum collections in Texas, the Biodiversity Research and Teaching Collections at Texas A&M University. Our sampling focused on the 9 amphibian species with the widest geographical distribution within the state, where we sub-sampled 30% of each species per decade from 1930 to present via skin swabs, totaling 1501 independent sampling events, and used quantitative real-time PCR (qPCR) to detect pathogen presence. We analyzed several geo-referenced variables describing climatic conditions to identify potential factors influencing the likelihood of presence of Bd using boosted regression trees. Our final model suggests the most influential variables are mean temperature of driest quarter, annual mean temperature, temperature annual range, and mean diurnal range. The most likely suitable range for Bd is currently found in the Blackland Prairie and Cross Timbers ecoregions. Results of our future (to the year 2040) projections suggest that Bd could expand its current distribution. Our model could play an important role when developing an integrated conservation plan through (1) focusing future field work on locations with a high likelihood of presence, (2) assisting in the choice of locations for restoration, and (3) developing future research plans including those necessary for projecting reactions to climate change. Our model also could integrate new presence data of Bd when they become available to enhance prediction precision.

Tubastraea coccinea is an invasive coral that has had ecological, economic, and social impacts in the Atlantic Ocean, the Caribbean Sea, and the Gulf of Mexico (GoM). Tubastraea coccinea is considered a major threat to marine biodiversity, whose occurrence in its non-native range has been associated with artificial structures such as oil/gas platforms and shipwrecks. A recent species distribution model identified important determinants of T. coccinea invasion in the northern GoM and projected its potential range expansion. However, the potential effects of anthropogenic factors were not considered. We used boosted regression trees to develop a species distribution model investigating the importance of oil/gas platforms and shipping fairways as determinants of T. coccinea invasion in the northern GoM. Our results indicate that maximum salinity, distance to platform, minimum nitrate, and mean pH were the first to fourth most influential variables, contributing 31.9%, 23.5%, 22.8%, and 21.8%, respectively, to the model. These findings highlight the importance of considering the effects of anthropogenic factors such as oil/gas platforms as potential determinants of range expansion by invasive corals. Such consideration is imperative when installing new platforms and when decommissioning retired platforms.