stable isotope

Invasive Seagrass and its effects on Juvenile Queen Conch

As invasive seagrass continues to expand and replace native species, populations such as the queen conch are seeing significant changes to their habitat and subsequent negative impact in food source availability. With potential consequence for the resilience of such species in a changing world. A recently published study from St. Barthelemy, St. Eustatius and St. Maarten, worked to understand how native and invasive seagrasses influence juvenile queen conch’s development by studying both dietary composition and growth rate.

 

This article was published in BioNews29

More information: Boman, E.M., Bervoets, T., de Graaf, M., Dewenter, J., Maitz, A., Meijer Zu Schlochtern, M.P., Stapel, J., Smaal, A.C., Nagelkerke, L.A.J., 2019. Diet and growth of juvenile queen conch Lobatus gigas (Gastropoda: Strombidae) in native, mixed and invasive seagrass habitats. MARINE ECOLOGY PROGRESS SERIES. Vol. 621: 143–154, 2019 https://doi.org/10.3354/meps12990

 

 

 

Date
2019
Data type
Media
Theme
Education and outreach
Research and monitoring
Geographic location
St. Eustatius
St. Maarten
Author

Diet and growth of juvenile queen conch Lobatus gigas (Gastropoda: Strombidae) in native, mixed and invasive seagrass habitats

ABSTRACT: Juvenile queen conch are primarily associated with native seagrass such as Thalassia
testudinum in large parts of their range in the Caribbean and the southern Gulf of Mexico. Here,
a number of non-native seagrass species have been introduced including Halophila stipulacea,
which is natural to the Red Sea and the Indo-Pacific. In the Caribbean, H. stipulacea often creates
dense continuous mats with little or no sediment exposed, compared to native seagrass, which
grows much less dense. We examined the diet and growth of juvenile conch in both native, mixed,
and invasive seagrass beds using stable isotope analysis and an in situ growth enclosure experiment.
Organic material in the sediment (i.e. benthic diatoms and particulate organic matter) was
found to be the most important source of carbon and nitrogen for juvenile queen conch in all 3
habitats investigated, and there was a significantly higher probability of positive growth in the
native seagrass compared to the invasive seagrass. Due to the importance of the organic material
in the sediment as a source of nutrition for juvenile conch, limited access to the sediment in the
invasive seagrass can potentially cause inadequate nutritional conditions to sustain high growth
rates. Thus, it is likely that there is a negative effect on juvenile queen conch growth currently
inhabiting invasive seagrass beds, compared to native seagrass beds, when other potential
sources of nutrition are not available.

Date
2019
Data type
Media
Theme
Education and outreach
Research and monitoring
Geographic location
St. Eustatius
St. Maarten