Metabolic responses of predators to prey density
The metabolic cost of foraging is the dark energy of ecological systems. It is much harder to observe and to measure than its beneficial counterpart, prey consumption, yet it is not inconsequential for the dynamics of prey and predator populations. Here I define the metabolic response as the change...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2022-12-01
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| Series: | Frontiers in Ecology and Evolution |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fevo.2022.980812/full |
| _version_ | 1811198294300295168 |
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| author | Henrique Corrêa Giacomini |
| author_facet | Henrique Corrêa Giacomini |
| author_sort | Henrique Corrêa Giacomini |
| collection | DOAJ |
| description | The metabolic cost of foraging is the dark energy of ecological systems. It is much harder to observe and to measure than its beneficial counterpart, prey consumption, yet it is not inconsequential for the dynamics of prey and predator populations. Here I define the metabolic response as the change in energy expenditure of predators in response to changes in prey density. It is analogous and intrinsically linked to the functional response, which is the change in consumption rate with prey density, as they are both shaped by adjustments in foraging activity. These adjustments are adaptive, ubiquitous in nature, and are implicitly assumed by models of predator–prey dynamics that impose consumption saturation in functional responses. By ignoring the associated metabolic responses, these models violate the principle of energy conservation and likely underestimate the strength of predator–prey interactions. Using analytical and numerical approaches, I show that missing this component of interaction has broad consequences for dynamical stability and for the robustness of ecosystems to persistent environmental or anthropogenic stressors. Negative metabolic responses – those resulting from decreases in foraging activity when more prey is available, and arguably the most common – lead to lower local stability of food webs and a faster pace of change in population sizes, including higher excitability, higher frequency of oscillations, and quicker return times to equilibrium when stable. They can also buffer the effects of press perturbations, such as harvesting, on target populations and on their prey through top-down trophic cascades, but are expected to magnify bottom-up cascades, including the effects of nutrient enrichment or the effects of altering lower trophic levels that can be caused by environmental forcing and climate change. These results have implications for any resource management approach that relies on models of food web dynamics, which is the case of many applications of ecosystem-based fisheries management. Finally, besides having their own individual effects, metabolic responses have the potential to greatly alter, or even invert, functional response-stability relationships, and therefore can be critical to an integral understanding of predation and its influence on population dynamics and persistence. |
| first_indexed | 2024-04-12T01:27:59Z |
| format | Article |
| id | doaj.art-eec4f77389994f8b98a8cf0478922252 |
| institution | Directory Open Access Journal |
| issn | 2296-701X |
| language | English |
| last_indexed | 2024-04-12T01:27:59Z |
| publishDate | 2022-12-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Ecology and Evolution |
| spelling | doaj.art-eec4f77389994f8b98a8cf04789222522022-12-22T03:53:35ZengFrontiers Media S.A.Frontiers in Ecology and Evolution2296-701X2022-12-011010.3389/fevo.2022.980812980812Metabolic responses of predators to prey densityHenrique Corrêa GiacominiThe metabolic cost of foraging is the dark energy of ecological systems. It is much harder to observe and to measure than its beneficial counterpart, prey consumption, yet it is not inconsequential for the dynamics of prey and predator populations. Here I define the metabolic response as the change in energy expenditure of predators in response to changes in prey density. It is analogous and intrinsically linked to the functional response, which is the change in consumption rate with prey density, as they are both shaped by adjustments in foraging activity. These adjustments are adaptive, ubiquitous in nature, and are implicitly assumed by models of predator–prey dynamics that impose consumption saturation in functional responses. By ignoring the associated metabolic responses, these models violate the principle of energy conservation and likely underestimate the strength of predator–prey interactions. Using analytical and numerical approaches, I show that missing this component of interaction has broad consequences for dynamical stability and for the robustness of ecosystems to persistent environmental or anthropogenic stressors. Negative metabolic responses – those resulting from decreases in foraging activity when more prey is available, and arguably the most common – lead to lower local stability of food webs and a faster pace of change in population sizes, including higher excitability, higher frequency of oscillations, and quicker return times to equilibrium when stable. They can also buffer the effects of press perturbations, such as harvesting, on target populations and on their prey through top-down trophic cascades, but are expected to magnify bottom-up cascades, including the effects of nutrient enrichment or the effects of altering lower trophic levels that can be caused by environmental forcing and climate change. These results have implications for any resource management approach that relies on models of food web dynamics, which is the case of many applications of ecosystem-based fisheries management. Finally, besides having their own individual effects, metabolic responses have the potential to greatly alter, or even invert, functional response-stability relationships, and therefore can be critical to an integral understanding of predation and its influence on population dynamics and persistence.https://www.frontiersin.org/articles/10.3389/fevo.2022.980812/fullmetabolic ecologypredator–prey interactionsfood web stabilityecosystem modelsgeneralized modelingtrophic cascades |
| spellingShingle | Henrique Corrêa Giacomini Metabolic responses of predators to prey density Frontiers in Ecology and Evolution metabolic ecology predator–prey interactions food web stability ecosystem models generalized modeling trophic cascades |
| title | Metabolic responses of predators to prey density |
| title_full | Metabolic responses of predators to prey density |
| title_fullStr | Metabolic responses of predators to prey density |
| title_full_unstemmed | Metabolic responses of predators to prey density |
| title_short | Metabolic responses of predators to prey density |
| title_sort | metabolic responses of predators to prey density |
| topic | metabolic ecology predator–prey interactions food web stability ecosystem models generalized modeling trophic cascades |
| url | https://www.frontiersin.org/articles/10.3389/fevo.2022.980812/full |
| work_keys_str_mv | AT henriquecorreagiacomini metabolicresponsesofpredatorstopreydensity |