Can DEB models infer metabolic differences between intertidal and subtidal morphotypes of the Antarctic limpet Nacella concinna (Strebel, 1908)?

Abstract

Studying the influence of changing environmental conditions on Antarctic marine benthic invertebrates is strongly constrained by limited access to the region, which poses difficulties to performing long-term experimental studies. Ecological modelling has been increasingly used as a potential alternative to assess the impact of such changes on species distribution or physiological performance. Among ecological models, the Dynamic Energy Budget (DEB) approach represents each individual through four energetic compartments (i.e. reserve, structure, maturation and reproduction) from which energy is allocated in contrasting proportions according to different life stages and to two forcing environmental factors (food resources and temperature). In this study, the example of an abundant coastal limpet, Nacella concinna (Strebel 1908), was studied. The species is known to have intertidal and subtidal morphotypes, genetically similar but physiologically and morphologically contrasting. The objectives of this paper are (1) to evaluate the potential of the DEB approach, and assess whether a DEB model can be separately built for the intertidal and subtidal morphotypes, based on a field experiment and data from literature and (2) to analyse whether models are contrasting enough to reflect the known physiological and morphological differences between the morphotypes. We found only minor differences in temperature-corrected parameter values between both populations, meaning that the observed differences can be only explained by differences in environmental conditions (i.e. DEB considered variables, food resources and temperature, but also other variables not considered by DEB). Despite the known morphological difference between the populations, the difference in shape coefficients was small. This study shows that even with the amount of data so far available in the literature, DEB models can already be applied to some Southern Ocean case studies, but, more data are required to accurately model the physiological and morphological differences between individuals.

Substantial intraspecific variation in energy budgets: biology or artefact?

“…Marn and colleagues (2019) found that DEB parameters differed between Mediterranean and North Atlantic loggerhead turtles, and that life-history differences between these populations could not be explained as a direct result of environmental differences between their respective habitats. In contrast, Guillaumot and colleagues (2020) were unable to determine differences in DEB parameters between intertidal and subtidal ecotypes of the Antarctic limpet, despite clear morphological divergence. As such, there is little consensus on the extent to which DEB parameters can vary within a single species.…”

“…This assumption is central to analyses of interspecific patterns of variation in DEB parameters, yet little is known about how much these parameters actually vary within species. To our knowledge, only two studies have employed DEB theory to quantify life-history differences between natural populations of the same species (Marn et al, 2019; Guillaumot et al, 2020). Marn and colleagues (2019) found that DEB parameters differed between Mediterranean and North Atlantic loggerhead turtles, and that life-history differences between these populations could not be explained as a direct result of environmental differences between their respective habitats.…”

Substantial intraspecific variation in energy budgets: Biology or artefact?

“…In contrast, Guillaumot et al. (2020) were unable to determine differences in DEB parameters between intertidal and subtidal ecotypes of the Antarctic limpet Nacella concinna , despite clear morphological divergence. There is little consensus on the extent to which DEB parameters vary within species, or on the causes of failure to detect differences in DEB parameters between ecologically and morphologically distinct populations.…”

The impact of seasonal regulation of metabolism on the life history of Antarctic krill

“…It has been successfully applied to a broad range of organisms such as Icelandic capelins (Einarsson et al 2011), the Pacific oyster (Ren and Ross 2001) and even endoparasitic wasps (Llandres et al 2015). Recent studies (Guillaumot et al 2020;Groeneveld et al 2020) emphasize how individual based modelling and DEB-theory can be especially useful for studying Antarctic species when habitat access is limited and data is sparse. The framework of bioenergetic modelling further holds the potential to project from individuals to population dynamics, which makes the development of a DEB-based krill model particularly interesting (Martin et al 2013).…”