The effect of climate change on the distribution of a tropical zoanthid (Palythoa caribaeorum) and its ecological implications

Abstract

Palythoa caribaeorum is a zoanthid often dominant in shallow rocky environments along the west coast of the Atlantic Ocean, from the tropics to the subtropics. This species has high environmental tolerance and is a good space competitor in reef environments. Considering current and future scenarios in the global climate regime, this study aimed to model and analyze the distribution of P. caribaeorum, generating maps of potential distribution for the present and the year 2100. The distribution was modeled using maximum entropy (Maxent) based on 327 occurrence sites retrieved from the literature. Calcite concentration, maximum chlorophyll-a concentration, salinity, pH, and temperature range yielded a model with the smallest Akaike information criterion (2649.8), and were used in the present and future distribution model. Data from the HadGEM2-ES climate model were used to generate the projections for the year 2100. The present distribution of P. caribaeorum shows that parts of the Brazilian coast, Caribbean Sea, and Florida are suitable regions for the species, as they are characterized by high salinity and pH and small temperature variation. An expansion of the species’ distribution was forecast northward under mild climate scenarios, while a decrease of suitable areas was forecast in the south. In the climate scenario with the most intense changes, P. caribaeorum would lose one-half of its suitable habitats, including the northernmost and southernmost areas of its distribution. The Caribbean Sea and northeastern Brazil, as well as other places under the influence of coastal upwellings, may serve as potential havens for this species.

Modeling impacts of climate change on the potential habitat of an endangered Brazilian endemic coral: Discussion about deep sea refugia

“…Even though the effects of each environmental variable on the population dynamics are unknown [101], the variables chosen to model the habitat suitability for M . harttii are in accordance with default conditions in previous studies on anthozoans [102].…”

Predicted Shifts in the Distributions of Atlantic Reef-Building Corals in the Face of Climate Change

“…Projecting future changes in the composition of species in reef ecosystems, albeit essential, is also challenging. Species distribution modeling (SDM) has become an important tool for ecologists [see Elith and Leathwick (2009) for a complete review], enabling predictions of current and future habitat suitability for a certain species (Cacciapaglia and van Woesik, 2018;Durante et al, 2018;Morato et al, 2020). These models incorporate the current empirical distribution of a given species (gathered from geolocated presence and absence data from surveys and global databases) and environmental data to establish habitats with the necessary conditions for that species to survive (Pearson and Dawson, 2003;Pearson et al, 2006;Wiens et al, 2009).…”

Effects of low pH and high temperature on two Palythoa spp. and predator–prey interactions in the subtropical eastern Atlantic

“…It has been shown that changes in pH conditions not only reduce calcification rates but also alter many physiological mechanisms in marine species (Arnold et al, 2012; Li & Gao, 2012). In fact, predicted models based on habitat suitability of P. caribaeorum in the West Atlantic suggested that 7.85 units of pH might be a barrier to its distribution pattern (Durante, Cruz & Lotufo, 2018). Biological performance of zooxanthellate zoantharians is highly mediated by the status of their symbionts, since species sustenance strongly depends on nutrients photosynthesized by Symbiodiniaceae.…”

“…also leads to modification of the composition of associated mesofauna (González‐Delgado et al, 2018) and even the whole intertidal and subtidal landscapes (López et al, 2020). In a climate change context, zoantharians may become ecologically dominant species to the detriment of other sessile organisms (Reimer et al, 2008; Durante, Cruz & Lotufo, 2018), compromising native ecosystems’ biodiversity and function.…”