The influence of plant defensive chemicals, diet composition, and winter severity on the nutritional condition of a free-ranging, generalist herbivore

Oikos ◽  
2016 ◽  
Vol 126 (2) ◽  
Author(s):  
Grace L. Parikh ◽  
Jennifer Sorensen Forbey ◽  
Brecken Robb ◽  
Rolf O. Peterson ◽  
Leah M. Vucetich ◽  
...  
Keyword(s):  
Diet Composition ◽  
Nutritional Condition ◽  
Generalist Herbivore ◽  
Free Ranging ◽  
Winter Severity

Resource partitioning by two syntopic sister species of butterflyfish (Chaetodontidae)

2017 ◽  
Vol 98 (7) ◽  
pp. 1767-1773 ◽  
Author(s):  
Ana M.R. Liedke ◽  
Roberta M. Bonaldo ◽  
Bárbara Segal ◽  
Carlos E.L. Ferreira ◽  
Lucas T. Nunes ◽  
...  
Keyword(s):  
Puerto Rico ◽  
Resource Partitioning ◽  
Diet Composition ◽  
Foraging Behaviour ◽  
Nutritional Condition ◽  
Ecological Communities ◽  
Substrate Selection ◽  
Feeding Rates ◽  
Bite Rate ◽  
Close Phylogenetic Relationship

Resource partitioning is considered one of the main processes driving diversification in ecological communities because it allows coexistence among closely related and ecologically equivalent species. We combined three complementary approaches, i.e. the evaluation of foraging behaviour, diet composition and nutritional condition (RNA:DNA ratio), to assess feeding by two closely related (sister) butterflyfishes that are syntopic in Puerto Rico. Chaetodon capistratus had a higher abundance and higher bite rate and selected octocorals and hard corals for feeding, whereas Chaetodon striatus fed preferentially on sandy substrates. Cnidarians and polychaetes were the most representative diet items for both species, but C. capistratus preferred the former (Feeding Index of 74.3%) and C. striatus the latter (Feeding Index of 60.4%). Similar RNA:DNA ratios for both species suggest that, although they differ in feeding rates and diet, C. capistratus and C. striatus have similar nutritional fitness. Therefore, these species are both zoobenthivores but show clear differences in their substrate selection. The differences in the use of foraging substrate by C. capistratus and C. striatus, despite their close phylogenetic relationship and similar diets, suggest that these species coexist by resource partitioning.

scholarly journals Covariation of diet and gut microbiome in African megafauna

2019 ◽  
Vol 116 (47) ◽  
pp. 23588-23593 ◽  
Author(s):  
Tyler R. Kartzinel ◽  
Julianna C. Hsing ◽  
Paul M. Musili ◽  
Bianca R. P. Brown ◽  
Robert M. Pringle
Keyword(s):  
Seasonal Variation ◽  
Gut Microbiome ◽  
Diet Composition ◽  
Dietary Diversity ◽  
Nutritional Ecology ◽  
East African ◽  
Large Herbivore ◽  
Environmental Pressures ◽  
Microbiome Composition ◽  
Free Ranging

A major challenge in biology is to understand how phylogeny, diet, and environment shape the mammalian gut microbiome. Yet most studies of nonhuman microbiomes have relied on relatively coarse dietary categorizations and have focused either on individual wild populations or on captive animals that are sheltered from environmental pressures, which may obscure the effects of dietary and environmental variation on microbiome composition in diverse natural communities. We analyzed plant and bacterial DNA in fecal samples from an assemblage of 33 sympatric large-herbivore species (27 native, 6 domesticated) in a semiarid East African savanna, which enabled high-resolution assessment of seasonal variation in both diet and microbiome composition. Phylogenetic relatedness strongly predicted microbiome composition (r = 0.91) and was weakly but significantly correlated with diet composition (r = 0.20). Dietary diversity did not significantly predict microbiome diversity across species or within any species except kudu; however, diet composition was significantly correlated with microbiome composition both across and within most species. We found a spectrum of seasonal sensitivity at the diet−microbiome nexus: Seasonal changes in diet composition explained 25% of seasonal variation in microbiome composition across species. Species’ positions on (and deviations from) this spectrum were not obviously driven by phylogeny, body size, digestive strategy, or diet composition; however, domesticated species tended to exhibit greater diet−microbiome turnover than wildlife. Our results reveal marked differences in the influence of environment on the degree of diet−microbiome covariation in free-ranging African megafauna, and this variation is not well explained by canonical predictors of nutritional ecology.

scholarly journals Varied diets, including broadleaved forage, are important for a large herbivore species inhabiting highly modified landscapes

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Annika M. Felton ◽  
Emma Holmström ◽  
Jonas Malmsten ◽  
Adam Felton ◽  
Joris P. G. M. Cromsigt ◽  
...  
Keyword(s):  
Food Availability ◽  
Diet Composition ◽  
Nutritional Composition ◽  
Large Herbivore ◽  
Large Herbivores ◽  
Winter Diet ◽  
Varied Diet ◽  
Survival And Reproduction ◽  
Herbivore Species ◽  
Free Ranging

AbstractDiet quality is an important determinant of animal survival and reproduction, and can be described as the combination of different food items ingested, and their nutritional composition. For large herbivores, human landscape modifications to vegetation can limit such diet-mixing opportunities. Here we use southern Sweden’s modified landscapes to assess winter diet mixtures (as an indicator of quality) and food availability as drivers of body mass (BM) variation in wild moose (Alces alces). We identify plant species found in the rumen of 323 moose harvested in Oct-Feb, and link variation in average calf BM among populations to diets and food availability. Our results show that variation in calf BM correlates with variation in diet composition, diversity, and food availability. A varied diet relatively rich in broadleaves was associated with higher calf BM than a less variable diet dominated by conifers. A diet high in shrubs and sugar/starch rich agricultural crops was associated with intermediate BM. The proportion of young production forest (0–15 yrs) in the landscape, an indicator of food availability, significantly accounted for variation in calf BM. Our findings emphasize the importance of not only diet composition and forage quantity, but also variability in the diets of large free-ranging herbivores.

scholarly journals The multidimensional nutritional niche of fungus-cultivar provisioning in free-ranging colonies of a neotropical leafcutter ant

2021 ◽  
Author(s):  
Antonin J.J. Crumière ◽  
Aidan James ◽  
Pol Lannes ◽  
Sophie Mallett ◽  
Anders Michelsen ◽  
...  
Keyword(s):  
Large Scale ◽  
Foraging Strategies ◽  
Generalist Herbivore ◽  
Leafcutter Ants ◽  
Microbial Symbiont ◽  
Foraging Niche ◽  
Generalist Insect ◽  
Atta Colombica ◽  
Free Ranging

AbstractThe foraging trails of Atta leafcutter colonies are among the most iconic scenes in Neotropical ecosystems, with thousands of ants carrying freshly cut plant fragments back to their nests where they are used to provision a fungal food crop. We tested a hypothesis that the fungal cultivar’s multidimensional requirements for macronutrients (protein and carbohydrates) and minerals (Al, Ca, Cu, Fe, K, Mg, Mn, Na, P and Zn) govern the foraging breadth of Atta colombica leafcutter ants in a Panamanian rainforest. Analyses of freshly cut plant fragments carried by leafcutter foragers showed that the combination of fruits, flowers, and leaves provide for a broad realized nutritional niche that can maximize cultivar’s performance. And, while the leaves that comprised the most harvested resource also delivered an intake target containing protein in excess of the amounts that can maximize cultivar growth, in vitro experiments showed that the minerals P, Al, and Fe can enhance the cultivar’s tolerance to protein-biased substrates, and potentially expand the ants’ foraging niche. Yet, the cultivar also exhibits narrow margins between mineral limitation and toxicity that may render plant fragments with seemingly optimal blends of macronutrients unsuitable for provisioning. Our approach highlights that optimal foraging is inherently multidimensional and links the foraging behavior of a generalist insect herbivore to the fundamental nutritional niche of its microbial symbiont.Significance StatementColonies of Atta colombica leafcutter ants can contain millions of specialized workers exhibiting large-scale generalist herbivory. Yet, this generalist foraging niche also depends on the poorly understood physiological needs of the ants’ domesticated fungal cultivar. We show the cultivar’s fundamental nutritional niche is broad for carbohydrates but narrower for protein and a suite of minerals, but that the cultivar’s sensitivity to excess protein is also mediated by Al, Fe, and P. More generally, this study decouples the multidimensional foraging strategies that enable a generalist herbivore to navigate a complex nutritional landscape and mix many imbalanced foods to achieve balanced cultivar provisioning.

Landscape fragmentation generates spatial variation of diet composition and quality in a generalist herbivore

Oecologia ◽  
2011 ◽  
Vol 167 (2) ◽  
pp. 401-411 ◽  
Author(s):  
Frial Abbas ◽  
Nicolas Morellet ◽  
A. J. Mark Hewison ◽  
Joël Merlet ◽  
Bruno Cargnelutti ◽  
...  
Keyword(s):  
Spatial Variation ◽  
Diet Composition ◽  
Landscape Fragmentation ◽  
Generalist Herbivore

The nutritional condition of moose co‐varies with climate, but not with density, predation risk or diet composition

Oikos ◽  
2021 ◽  
Vol 2022 (1) ◽  
Author(s):  
Sarah R. Hoy ◽  
Jennifer S. Forbey ◽  
Daniel P. Melody ◽  
Leah M. Vucetich ◽  
Rolf O. Peterson ◽  
...  
Keyword(s):  
Predation Risk ◽  
Diet Composition ◽  
Nutritional Condition
Sign in / Sign up

Export Citation Format

Share Document