scholarly journals Linking alternative food sources to winter habitat selection of herbivores in overbrowsed landscapes

2011 ◽  
Vol 76 (3) ◽  
pp. 544-556 ◽  
Author(s):  
Ariane Massé ◽  
Steeve D. Côté
Animals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2454
Author(s):  
Yue Sun ◽  
Yanze Yu ◽  
Jinhao Guo ◽  
Minghai Zhang

Single-scale frameworks are often used to analyze the habitat selections of species. Research on habitat selection can be significantly improved using multi-scale models that enable greater in-depth analyses of the scale dependence between species and specific environmental factors. In this study, the winter habitat selection of red deer in the Gogostaihanwula Nature Reserve, Inner Mongolia, was studied using a multi-scale model. Each selected covariate was included in multi-scale models at their “characteristic scale”, and we used an all subsets approach and model selection framework to assess habitat selection. The results showed that: (1) Univariate logistic regression analysis showed that the response scale of red deer to environmental factors was different among different covariate. The optimal scale of the single covariate was 800–3200 m, slope (SLP), altitude (ELE), and ratio of deciduous broad-leaved forests were 800 m in large scale, except that the farmland ratio was 200 m in fine scale. The optimal scale of road density and grassland ratio is both 1600 m, and the optimal scale of net forest production capacity is 3200 m; (2) distance to forest edges, distance to cement roads, distance to villages, altitude, distance to all road, and slope of the region were the most important factors affecting winter habitat selection. The outcomes of this study indicate that future studies on the effectiveness of habitat selections will benefit from multi-scale models. In addition to increasing interpretive and predictive capabilities, multi-scale habitat selection models enhance our understanding of how species respond to their environments and contribute to the formulation of effective conservation and management strategies for ungulata.


2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 1418-1418
Author(s):  
Daniel Ibsen ◽  
Marianne Jakobsen ◽  
Jytte Halkjær ◽  
Erik Parner ◽  
Kim Overvad

Abstract Objectives We investigated whether decreasing the intake of red meat and simultaneously increasing the intake of alternative food sources of protein affects the risk of type 2 diabetes compared with no changes in the substituted foods. We also examined interaction with the age at which participants changed their diet. Methods We used the Danish Diet, Cancer and Health cohort including men and women, two measures of diet taken roughly 5 years apart using food frequency questionnaires and information on incident type 2 diabetes derived from the Danish National Diabetes Register (n = 39,349; aged 55 to 72 years at the second diet measure; n cases = 3759). The pseudo-observation method was used to estimate the average exposure effect of decreasing the intake of red meat (processed and unprocessed) while increasing the intake of either poultry, fish, cheese, eggs or whole grains compared with no changes in the substituted foods on the subsequent 10-year risk of development type 2 diabetes. Results In multivariable adjusted models, we found that replacing 1 serving/day (100 g) of red meat with 1 serving/day of eggs (50 g) (risk difference −2.4%, 95% confidence interval −3.7 to −1.1%) or whole grains (30 g) (−1.4%, −2.2 to −0.6%) was associated with a reduced risk of type 2 diabetes. No effects were observed for other replacements. In general, the lowest risk was observed for replacements at age 55 years compared with older ages (up to 70 years) for all replacements. Conclusions Replacing red meat with eggs or whole grains may reduce the risk of type 2 diabetes compared with no changes in the substituted foods. Changing red meat intake in midlife may be more beneficial than at older ages. Funding Sources Aarhus University.


Hydrobiologia ◽  
2013 ◽  
Vol 735 (1) ◽  
pp. 263-276 ◽  
Author(s):  
Soledad Marroni ◽  
Carlos Iglesias ◽  
Néstor Mazzeo ◽  
Juan Clemente ◽  
Franco Teixeira de Mello ◽  
...  

2017 ◽  
Vol 52 (3) ◽  
pp. 149-160 ◽  
Author(s):  
Carmen Silvia Soares Pires ◽  
Mayra Pimenta ◽  
Renata Alves da Mata ◽  
Lucas Machado de Souza ◽  
Débora Pires Paula ◽  
...  

Abstract: The objective of this work was to determine the survival pattern of the cotton boll weevil during fallow in Midwestern Brazil. The percentage of adults that remained in the cotton reproductive structures, the percentage of adults searching for shelters, and the longevity of adults fed on pollen and nectar as alternative food sources were determined. For this, four populations were sampled in cotton squares and bolls, totaling 11,293 structures, from 2008 to 2012. The emergency of cotton weevil adults was monitored from the collection of the structures until the next cotton season. In the laboratory, newly-emerged adults were fed on hibiscus or Spanish needle, and their life span was monitored individually. Most adults (85.73%) left the reproductive structures, regardless of the cotton plant phenology, up to 49 days after the structures were collected. One individual (0.0002%) from 5,544 adults was found alive after the fallow period. The diet with hibiscus and Spanish needle provided adult longevity of 76±38 days, which was enough time for adults to survive during the fallow period. Most of the boll weevils leave the cotton structures at the end of harvest, survive using alternative food sources, and do not use cotton plant structures as shelter during the legal cotton fallow period in Midwestern Brazil.


Author(s):  
Arne Deknock ◽  
Frank Pasmans ◽  
Robby van Leeuwenberg ◽  
Sarah Van Praet ◽  
Stijn Bruneel ◽  
...  

Author(s):  
C.P. Santos ◽  
A.B. Coutinho ◽  
E. Hajdu

Sea urchins were collected in August 1999, at Salvador (Todos os Santos Bay, State of Bahia, Brazil). Twenty out of 20 Eucidaris tribuloides sea urchins studied had sponge remains in their guts, 12 of which, in large enough quantities to discard the hypothesis of sponge contamination on other food items. No other macroscopic evidence of alternative food sources has been encountered. Sponges found in large enough quantities were classified in seven genera, spread over seven families and five orders of the Demospongiae. Among the commonest sponges were Haliclona spp. and Iotrochota birotulata. The results show clearly the spongivorous habit of E. tribuloides at the studied site.


2017 ◽  
Vol 78 (2) ◽  
pp. 211-216 ◽  
Author(s):  
M. S. de Lima ◽  
J. W. S. Melo ◽  
R. Barros

Abstract The predator Brumoides foudrasii (Mulsant) (Coleoptera, Coccinellidae) has been naturally found in plants infested by mealybugs. In this study, the striped mealybug Ferrisia dasylirii (Cockerell) (Hemiptera, Pseudococcidae) and Anagasta kuehniella Zeller (Lepidoptera, Pyralidae) eggs were evaluated as diets for the development and reproduction of B. foudrasii. Brumoides foudrasii immatures developed faster when fed with A. kuehniella eggs than when fed with F. dasylirii. However, the survival and longevity of B. foudrasii adults were not affected by the diets. Oviposition was more frequent when B. foudrasii females were fed with F. dasylirii (95%) than those fed with A. kuehniella eggs (65%). Brumoides foudrasii females fed with F. dasylirii were 2.5 times more fecund than those fed with A. kuehniella eggs. Although both diets may be considered proper for B. foudrasii, A. kuehniella eggs were more suitable for immature development, while F. darsyrili provided more nutritious resources for adult biological parameters as oviposition period, egg viability and fecundity. These results suggests that this predator can play an important role in regulating populations of the stripped mealybug F. dasylirii in the field.


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