I am a postdoc Fellow at the Mediterranean Institute for Advanced Studies working in coastal systems in the Dra. Fiona Tomas lab. My research interest is to understand how environmental factors or other ecological state changes affect the processes and mechanisms of coastal systems at different levels, from individuals to communities, and at different spatial and temporal scales. Most of my work focuses on marine macrophytes and fish communities and my research is motivated by dual goals of advancing ecological knowledge and influencing management decisions. To this end, I take an integrative perspective in physiology and ecology combining observational and experimental approaches, and modelling tools.

My current research is related to seagrass systems examining how ecological changes such as invasive species or human stressors affect them. Also, I am collaborating in a project looking at the dynamics and accumulation of microplastics in these systems.

In my previous postdoc at Florida State University I was working in the Dr. Rassweiller lab using quantitative ecology to examine the environmental and ecological drivers of change in coastal communities and also on improving methods for monitoring marine biodiversity.

In my doctoral work at the Mediterranean Institute for Advanced Studies, I studied the effects that changes in environmental factors (e.g., eutrophication, warming and acidification) have on seagrass-herbivore interactions by examining a wide range of plant responses and at different plant life stages and how some of these changes influenced herbivore behavior. During my PhD I visited different research groups and institutions collaborating with international researchers and I try to extend this collaborative spirit everywhere I work.

I enjoy sharing my research with the public and inspiring students. I have participated in outreach activities such as lab open doors and women in science events and judged regional science fairs. Also, I am a scientist you can Skype in the skype a scientist program. For more information see my list of publications and C.V.

[19] McHenry, J., A. Rassweiler, G. Hernan, A.K. Dubel, C. Curtin, J. Barzak, N. Varias, S.E. Lester (2023): Geographic variation in organic carbon storage by seagrass beds. Limnology and Oceanography. doi:10.1002/lno.12343 Link

Abstract: Since seagrasses are efficient sinks for marine organic carbon, there is growing interest in incorporating seagrass protection and restoration into climate mitigation schemes, that is, offering credit for accumulated carbon to offset carbon dioxide emissions. However, patterns and drivers of organic carbon storage by seagrasses are not well resolved, especially at scales relevant to management decisions. Here, we quantified geographic variation in stand- ing stocks of sedimentary organic carbon (Mg Corg ha-1) associated with seagrasses along the northern Florida Gulf Coast using field surveys and sediment cores. We measured plant biomass, organic carbon, and sediment composi- tion in each core. Using a multivariate modeling approach, we evaluated the relative importance of ecological, physical, oceanographic, and seascape drivers, developing the first spatially explicit predictions of seagrass- associated carbon stocks for this region. Applying model predictions to confirmed seagrass beds and potential recovery areas, we also estimated the carbon storage value of potential seagrass conservation and restoration as the resulting stock enhancement value per hectare of seagrass (Δ Mg Corg ha-1). We found that organic carbon stored by seagrass sediments varied considerably across this region, with stocks significantly increasing with seagrass cover, proximity to oyster reefs, and distance from river outlets, highlighting potential synergies for coordinated management. We also found that current seagrass beds could offer nearly double the carbon storage value of poten- tial recovery areas, emphasizing the importance of conservation as well as restoration. Our results have important implications for management, restoration, and understanding biogeographic patterns of seagrass ecosystem services.

[18] Mañez-Crespo, Tomas F., Fernandez-Torquemada Y., Royo L., Espino F., Antich L., Bosch N. E., Castejón I., Hernán G., Marco-Méndez C., Mateo-Ramírez A., Pereda-Briones L., del Pilar-Ruso Y., Terrados J., Tuya F. (2022): Variation in fish abundance, diversity and assemblage structure in seagrass meadows across the Atlanto-Mediterranean province. Diversity 14 (10), 808. doi:10.3390/d14100808 Link [PDF]

Abstract: Seagrasses worldwide provide key habitats for fish assemblages. Biogeographical disparities in ocean climate conditions and seasonal regimes are well-known drivers of the spatial and temporal variation in seagrass structure, with potential effects on associated fish assemblages. Whether taxonomically disparate fish assemblages support a similar range of ecological functions remains poorly tested in seagrass ecosystems. In this study, we examined variation in the abundance, diversity (from a taxonomic and functional perspective), and assemblage structure of fish community inhabiting nine meadows of the seagrass Cymodocea nodosa across three regions in the Mediterranean (Mallorca and Alicante) and the adjacent Atlantic (Gran Canaria), and identified which attributes typifying the structure of meadows, and large-scale variability in ocean climate, contributed most to explaining such ecological variation. Despite a similar total number of species between Mallorca and Gran Canaria, the latter region had more taxonomically and functionally diverse fish assemblages relative to the western Mediterranean regions, which translated into differences in multivariate assemblage structure. While variation in the abundance of the most conspicuous fish species was largely explained by variation in seagrass structural descriptors, most variation in diversity was accounted for by a descriptor of ocean climate (mean seasonal SST), operating at regional scales. Variation in fish assemblage structure was, to a lesser extent, also explained by local variability in seagrass structure. Beyond climatic drivers, our results suggest that lower temporal variability in the canopy structure of C. nodosa meadows in Gran Canaria provides a more consistent source of food and protection for associated fish assemblages, which likely enhances the more abundant and diverse fish assemblages there.

[17] Mateo-Ramirez A., Mañez-Crespo J., Royo L., Tuya F., Castejón-Silvo, Hernán G., Pereda-Briones L., Terrados J. and Tomas F. (2022) A Tropical Macroalga (Halimeda incrassata) Enhances Diversity and Abundance of Epifaunal Assemblages in Mediterranean Seagrass Meadows. Front. Mar. Sci. 9:886009. doi: 10.3389/fmars.2022.886009 Link

Abstract: The introduction and successful expansion of tropical species into temperate systems is being exacerbated by climate change, and it is particularly important to identify the impacts that those species may have, especially when habitat-forming species are involved. Seagrass meadows are key shallow coastal habitats that provide critical ecosystem services worldwide, and they are threatened by the arrival of non-native macroalgae. Here, we examined the effects of Halimeda incrassata, a tropical alga that has recently colonized the Mediterranean Sea, on epifaunal assemblages associated with Cymodocea nodosa seagrass meadows of Mallorca Island (Western Mediterranean Sea). This invasive macroalga is an ecological engineer and thus has a high potential of modifying native habitats. A seagrass meadow colonized by H. incrassata exhibited important changes on associated epifaunal assemblages, with an increase in abundance and diversity, particularly driven by higher abundances of Gammaridae, Polychaeta, Copepoda and Caprellidae. Given the key ecological contribution of epifauna to food webs, these alterations will likely have important implications for overall food web structure and ecosystem functioning of native ecosystems.