TY - JOUR
T1 - Direct observation and quantitative characterization of chemotactic behaviors in Caribbean coral larvae exposed to organic and inorganic settlement cues
AU - Deshpande, Koumudhi
AU - Gysbers, Daniel
AU - Yus, Joaquin
AU - van Bendegom, Daan
AU - Nixon, Emily
AU - McClintock, Rayna
AU - Quinlan, Zachary A.
AU - Marhaver, Kristen L.
AU - Kelly, Linda Wegley
AU - Espinosa-Marzal, Rosa M.
AU - Johnson, Amy J.Wagoner
AU - Juarez, Gabriel
N1 - The authors acknowledge the National Science Foundation (NSF) for funding through the ECO-CBET program (Award #2133675) which supported the work of K.D., J.Y., A.J.W.J., R.M.E-M., G.J., and K.L.M. L.W.K., E.N., and R.M. were supported by the NSF ECO-CBET Program (Award #2133474). Z.A.Q. was supported by the NSF Graduate Research Fellowship Program (Award #2019252845). A.J.W.J. is a Chan Zuckerberg Biohub Chicago Investigator. The authors thank the Government of Cura\u00E7ao, Ministry of Health, Environment, and Nature (GMN), for research and collecting permits provided to CARMABI. The authors thank Daisy Flores and Mark Vermeij for their assistance with the collection and care of coral larvae. The authors would also like to thank the staff at CARMABI and The DiveShop Cura\u00E7ao during the 2022 spawning season. Finally, the authors would like to thank the Illinois Statistics Consulting team\u2014specifically Maggie Smith and Rik Ray for helpful conversations on statistical analysis.
PY - 2025/3/24
Y1 - 2025/3/24
N2 - Upon their arrival in the water column, coral larvae use physical and chemical cues to navigate toward a suitable habitat and begin their settlement process. To engineer substrates that influence settlement, it is important to have quantitative data about the types and concentrations of chemicals that elicit desired behavioral responses before and after contact with the substrate. Here, we quantified the behavioral and morphological responses of coral larvae (Colpophyllia natans and Orbicella faveolata) to crustose coralline algae exudates (CCA) and ions found in coral skeletons using chemotactic assays in microfluidic channels. Multiple larvae in each channel were tracked over 30 min to quantify their overall attraction or repulsion to the presence of various dissolved chemical cues. Larvae showed repulsion to, attraction to both and CCA exudates, and both attraction and repulsion to, depending on the concentration. The behavioral and morphological changes exhibited by individual larvae were investigated as well. Using particle tracking methods to quantify larval behavior, we found that the typically straight swimming larvae of C. natans increased turning behavior in regions with high concentrations of CCA exudates and, a behavior associated with local searching, while they decreased turning behavior near high concentrations of. We also found that larvae shrink in length when exposed to 50× the seawater concentration of calcium, a potential stress or escape response, while these larvae elongated when exposed to CCA exudates, a morphological response associated with benthic contact and crawling. These results highlight the value of direct observation in understanding the interplay between coral larvae and their chemical environment. Incorporating cues such as calcium or CCA exudates into artificial substrates can elicit specific behavioral and physical changes in coral larvae, thereby enhancing settlement and contributing to reef restoration efforts.
AB - Upon their arrival in the water column, coral larvae use physical and chemical cues to navigate toward a suitable habitat and begin their settlement process. To engineer substrates that influence settlement, it is important to have quantitative data about the types and concentrations of chemicals that elicit desired behavioral responses before and after contact with the substrate. Here, we quantified the behavioral and morphological responses of coral larvae (Colpophyllia natans and Orbicella faveolata) to crustose coralline algae exudates (CCA) and ions found in coral skeletons using chemotactic assays in microfluidic channels. Multiple larvae in each channel were tracked over 30 min to quantify their overall attraction or repulsion to the presence of various dissolved chemical cues. Larvae showed repulsion to, attraction to both and CCA exudates, and both attraction and repulsion to, depending on the concentration. The behavioral and morphological changes exhibited by individual larvae were investigated as well. Using particle tracking methods to quantify larval behavior, we found that the typically straight swimming larvae of C. natans increased turning behavior in regions with high concentrations of CCA exudates and, a behavior associated with local searching, while they decreased turning behavior near high concentrations of. We also found that larvae shrink in length when exposed to 50× the seawater concentration of calcium, a potential stress or escape response, while these larvae elongated when exposed to CCA exudates, a morphological response associated with benthic contact and crawling. These results highlight the value of direct observation in understanding the interplay between coral larvae and their chemical environment. Incorporating cues such as calcium or CCA exudates into artificial substrates can elicit specific behavioral and physical changes in coral larvae, thereby enhancing settlement and contributing to reef restoration efforts.
UR - http://www.scopus.com/inward/record.url?scp=105000632691&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=105000632691&partnerID=8YFLogxK
U2 - 10.1038/s41598-025-93194-z
DO - 10.1038/s41598-025-93194-z
M3 - Article
C2 - 40128257
AN - SCOPUS:105000632691
SN - 2045-2322
VL - 15
JO - Scientific reports
JF - Scientific reports
IS - 1
M1 - 10173
ER -