Abstract
Upwelling is known to affect the ecology and life history of temperate nearshore organisms, and these effects are thought to be mediated by changes in temperature and food supply. However, little information is available for tropical systems. To understand how changes in the intensity of upwelling might impact marine invertebrates, we tested how factorial combinations of temperature, salinity, and phytoplankton availability affected growth and reproduction of a common intertidal snail, Crepidula cf. marginalis. We used temperatures typical of nonupwelling (29°C), moderate (26°C) and severe (23°C) upwelling, salinities typical of nonupwelling (30 ppt) and upwelling (34 ppt) and a good diet (Isochrysis) and a better diet (Isochrysis and Tetraselmis) as a proxy for increased productivity during upwelling. Overall, temperature and diet had consistent effects on body size, with better food and lower temperatures promoting larger size, as well as promoting shorter time to first reproduction. Diet had the largest effects on clutch size, with clutch size increasing with better diet. Temperature had the largest effect on offspring size and the frequency of discarded broods; offspring size decreased with increasing temperature and the frequency of discarded broods also decreased with increasing temperatures. We found no significant 3rd order interactions and few significant strong 2nd order interactions, which have often been found in similar experimental studies using stressful treatments. For this tropical slipper limpet, the effect of higher food and cooler temperatures during upwelling appears to be positive, promoting higher growth rates, larger clutch sizes, and larger offspring size suggesting that both factors likely play an important role underlying reproductive responses to upwelling. Climatic changes, like El Niño, which suppress upwelling in the Bay of Panama, appear likely to negatively impact this species.
Highlights
Multiple stressor experiments are becoming increasingly common as researchers focus effort on understanding and predicting the impacts of global change (Gunderson, Armstrong, & Stillman, 2016; Todgham & Stillman, 2013)
Crepidula cf. marginalis were collected at Playa Venado (8.892°N, 79.597°W) near the town of Veracruz on the Pacific coast of the Bay of Panama in November 2017
We provided 20 × 106 cells/ml daily of Isochrysis galbana for snails in the good diet treatment, and for the better diet, we provide the same amount of Isochrysis and 3.33 × 106 cells/ ml of Tetraselmis sp
Summary
Multiple stressor experiments are becoming increasingly common as researchers focus effort on understanding and predicting the impacts of global change (Gunderson, Armstrong, & Stillman, 2016; Todgham & Stillman, 2013). In tropical systems switches between monsoonal and nonmonsoonal conditions, which are driven by changes in the position of the intertropical convergence zone (ITCZ), may dominate the seasonal cycles of many organisms (e.g., Gaonkar et al, 2012; Pillai & Subramoniam, 1984; Wai et al, 2012) Such patterns are already impacted by El Niño-Southern Oscillation (ENSO; the cycle of sea surface temperatures in the central and eastern Pacific, which has global climate consequences through shifts in atmospheric circulation; see Glynn, 1988) events which, for example, increase the length of the dry season in Panama. To understand how changes in the duration and intensity of the upwelling season might impact marine invertebrates, we tested how factorial combinations of temperature, salinity, and phytoplankton availability affected growth and reproduction of a common intertidal snail These factors co-vary in nature but may act independently or synergistically, and this approach allowed us to disentangle these effects. Females produce multiple broods in a year, and species in the family are extremely abundant and diverse in this region, suggesting they are well-suited to the prevailing environmental conditions
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
