scholarly journals Behavioral repeatability and foraging performance in wild free-flying nectarivorous bats (Glossophaga commissarisi)

2018 ◽  
Author(s):  
Vladislav Nachev ◽  
York Winter

ABSTRACTAnimal individuals show patterns of behavior that are stable within individuals but different among individuals. Such individual differences are potentially associated with differences in foraging efficiency and in fitness. Furthermore, behavioral responses may be correlated in specific suites of so called behavioral syndromes that are consistent across different contexts and with time. Here we present a field investigation on individual differences between wild, free-flying nectarivorous bats (Glossophaga commissarisi) in the foraging context. We further investigated how individual differences effect foraging performance, and we examined their interdependence within hypothesized behavioral syndrome structures. Free-ranging bats were individually identified as they visited an array of 24 artificial flowers with nectar of high or low sugar concentration. We found that three behavioral measures of foraging behavior were individually stable over the two-month observation period. We investigated the link between individual behavioral measures and measures of foraging performance using generalized linear mixed models. Individual measures of foraging performance showed significant repeatability, and we found evidence that bats making more visits per bout tend to be slower in learning to avoid unprofitable flowers. We used a multi-response generalized linear mixed model to estimate between-individual correlations and compare hypothesized syndrome structures. There were no clear patterns of between-individual correlations among the behavioral measures in our study, despite the measures exhibiting significant repeatability. This may indicate that foraging performance depends on multiple individual behavior dimensions that are not adequately described by simple models of behavior syndromes.


2008 ◽  
Vol 88 (6) ◽  
pp. 1153-1157 ◽  
Author(s):  
Bruno Díaz López ◽  
Julia Andrea Bernal Shirai ◽  
Alberto Bilbao Prieto ◽  
Paula Méndez Fernández

Solitary wild bottlenose dolphins and man frequenting the same small areas makes boat interaction more or less inevitable. Here we provide the first quantified data about solitary bottlenose dolphin diving behaviour in the presence and absence of boats. Over 110 hours were spent observing a solitary bottlenose dolphin within a 6 km2 bay on the north-western coast of Spain from April to August 2005. A generalized linear mixed model explaining 77.3% of the variability of duration of dives indicated that the animal did not vary its diving activity in function of the presence of boats. However, the length of dives was related with the behavioural events prior to dive. Dolphin activity was characterized by mean dive intervals (mean = 62.6 seconds) related to a predominance of foraging behaviour. Because of the frequent presence of boats and the manner in which they moved, the dolphin may have become accustomed to their presence. The data reported here could be used to implement precautionary management proposals that take into account the potential effects of boat presence on bottlenose dolphins.



2018 ◽  
Vol 48 (4) ◽  
pp. 547-563 ◽  
Author(s):  
Daniel Zimprich

Recognition of popular songs from one’s past shows a phenomenon that is known as a “reminiscence bump” from autobiographical memory research, namely, the increased recognition performance of songs from one’s youth and early adulthood. As a first goal of the present study, a non-linear functional relation between popular song recognition performance and song-specific age of an individual was examined. As a second goal, individual differences in recognition performance curves were taken into account by including random effects. The third goal was to explain individual differences by including predictor variables. The sample comprised 90 participants aged 70 to 75 years. Participants listened to excerpts of 51 songs of the German charts from the years 1945 to 1995. Results show that the average bump performance was 75%, that the bump was located at about 17 years of age, and that the inflection point was located at 31 years. Individual differences could be explained by the number of correctly recognized songs, musical taste during one’s youth, and the frequency and preference of listing to bump songs. To conclude, an individual differences approach based on a non-linear function relation has been found to be a promising way to understand why popular songs from one’s youth are remembered better.



2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Agnieszka Sergiel ◽  
Marc Cattet ◽  
Luciene Kapronczai ◽  
David M Janz ◽  
Nuria Selva ◽  
...  

Abstract Cortisol concentrations in hair are used increasingly as a biomarker of long-term stress in free-ranging wildlife. Cortisol is believed to be integrated into hair primarily during its active growth phase, typically occurring over weeks to months or longer periods, depending on latitude. Cortisol concentrations in hair thus reflect the activity of the hypothalamic–pituitary–adrenal axis over this time. However, local, independent cortisol secretion within the skin, which includes hair follicles, may also contribute to cortisol levels in growing hair. Methodological differences between studies include the measurement of cortisol in only the hair shaft (i.e. follicle absent, as with shaved hair) versus the whole hair (i.e. follicle present, as with plucked hair). If the concentration of cortisol in the follicle is high enough to influence the overall hair cortisol concentration (HCC), this could confound comparisons between studies using different types of hair samples (hair shafts vs. whole hair) and collection methods. Here, we test the hypothesis that cortisol present in follicles influences HCC. We compared HCC in paired subsamples of hair with and without follicles from 30 free-ranging Scandinavian brown bears (Ursus arctos) and observed significantly greater HCC in samples with follicles present. The effect of follicles remained significant also with sex and age of sampled bears taken into account in a linear mixed model. Finally, we provide an overview of collection methods and types of hair samples used for HCC analysis in 77 studies dealing with stress in wild mammal species. Our findings highlight the need to unify methods of hair collection and preparation to allow for valid comparisons, and to optimize labour input in ecophysiological studies.



2020 ◽  
Author(s):  
James L. Peugh ◽  
Sarah J. Beal ◽  
Meghan E. McGrady ◽  
Michael D. Toland ◽  
Constance Mara


2020 ◽  
Vol 641 ◽  
pp. 159-175
Author(s):  
J Runnebaum ◽  
KR Tanaka ◽  
L Guan ◽  
J Cao ◽  
L O’Brien ◽  
...  

Bycatch remains a global problem in managing sustainable fisheries. A critical aspect of management is understanding the timing and spatial extent of bycatch. Fisheries management often relies on observed bycatch data, which are not always available due to a lack of reporting or observer coverage. Alternatively, analyzing the overlap in suitable habitat for the target and non-target species can provide a spatial management tool to understand where bycatch interactions are likely to occur. Potential bycatch hotspots based on suitable habitat were predicted for cusk Brosme brosme incidentally caught in the Gulf of Maine American lobster Homarus americanus fishery. Data from multiple fisheries-independent surveys were combined in a delta-generalized linear mixed model to generate spatially explicit density estimates for use in an independent habitat suitability index. The habitat suitability indices for American lobster and cusk were then compared to predict potential bycatch hotspot locations. Suitable habitat for American lobster has increased between 1980 and 2013 while suitable habitat for cusk decreased throughout most of the Gulf of Maine, except for Georges Basin and the Great South Channel. The proportion of overlap in suitable habitat varied interannually but decreased slightly in the spring and remained relatively stable in the fall over the time series. As Gulf of Maine temperatures continue to increase, the interactions between American lobster and cusk are predicted to decline as cusk habitat continues to constrict. This framework can contribute to fisheries managers’ understanding of changes in habitat overlap as climate conditions continue to change and alter where bycatch interactions could occur.



2019 ◽  
Vol 24 (2) ◽  
pp. 200-208
Author(s):  
Ravindra Arya ◽  
Francesco T. Mangano ◽  
Paul S. Horn ◽  
Sabrina K. Kaul ◽  
Serena K. Kaul ◽  
...  

OBJECTIVEThere is emerging data that adults with temporal lobe epilepsy (TLE) without a discrete lesion on brain MRI have surgical outcomes comparable to those with hippocampal sclerosis (HS). However, pediatric TLE is different from its adult counterpart. In this study, the authors investigated if the presence of a potentially epileptogenic lesion on presurgical brain MRI influences the long-term seizure outcomes after pediatric temporal lobectomy.METHODSChildren who underwent temporal lobectomy between 2007 and 2015 and had at least 1 year of seizure outcomes data were identified. These were classified into lesional and MRI-negative groups based on whether an epilepsy-protocol brain MRI showed a lesion sufficiently specific to guide surgical decisions. These patients were also categorized into pure TLE and temporal plus epilepsies based on the neurophysiological localization of the seizure-onset zone. Seizure outcomes at each follow-up visit were incorporated into a repeated-measures generalized linear mixed model (GLMM) with MRI status as a grouping variable. Clinical variables were incorporated into GLMM as covariates.RESULTSOne hundred nine patients (44 females) were included, aged 5 to 21 years, and were classified as lesional (73%), MRI negative (27%), pure TLE (56%), and temporal plus (44%). After a mean follow-up of 3.2 years (range 1.2–8.8 years), 66% of the patients were seizure free for ≥ 1 year at last follow-up. GLMM analysis revealed that lesional patients were more likely to be seizure free over the long term compared to MRI-negative patients for the overall cohort (OR 2.58, p < 0.0001) and for temporal plus epilepsies (OR 1.85, p = 0.0052). The effect of MRI lesion was not significant for pure TLE (OR 2.64, p = 0.0635). Concordance of ictal electroencephalography (OR 3.46, p < 0.0001), magnetoencephalography (OR 4.26, p < 0.0001), and later age of seizure onset (OR 1.05, p = 0.0091) were associated with a higher likelihood of seizure freedom. The most common histological findings included cortical dysplasia types 1B and 2A, HS (40% with dual pathology), and tuberous sclerosis.CONCLUSIONSA lesion on presurgical brain MRI is an important determinant of long-term seizure freedom after pediatric temporal lobectomy. Pediatric TLE is heterogeneous regarding etiologies and organization of seizure-onset zones with many patients qualifying for temporal plus nosology. The presence of an MRI lesion determined seizure outcomes in patients with temporal plus epilepsies. However, pure TLE had comparable surgical seizure outcomes for lesional and MRI-negative groups.



Author(s):  
Miriam Romero-López ◽  
María Carmen Pichardo ◽  
Ana Justicia-Arráez ◽  
Judit Bembibre-Serrano

The objective of this study is to measure the effectiveness of a program on improving inhibitory and emotional control among children. In addition, it is assessed whether the improvement of these skills has an effect on the reduction of aggressive behavior in pre-school children. The participants were 100 children, 50 belonging to the control group and 50 to the experimental group, aged between 5 and 6 years. Pre-intervention and post-intervention measures of inhibitory and emotional control (BRIEF-P) and aggression (BASC) were taken. A Generalized Linear Mixed Model analysis (GLMM) was performed and found that children in the experimental group scored higher on inhibitory and emotional control compared to their peers in the control group. In addition, these improvements have an effect on the decrease in aggressiveness. In conclusion, preventive research should have among its priorities the design of such program given their implications for psychosocial development.



Forests ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 118
Author(s):  
Lunel Joseph ◽  
Raúl Marino Yaranga Cano ◽  
Marco Arizapana-Almonacid ◽  
Marcela Venelli Pyles ◽  
Flávia Freire de Siqueira ◽  
...  

Research Highlights: Families more dependent on crops as the main source of income of properties have a greater intention of restoring Polylepis forest areas. However, this intention reduces with the increase of family dependence on subsistence products supplied by Polylepis forests. Properties where the chances of restoration of Polylepis forests are greater are those where the educational and technical level is better. Objectives: We aimed to comprehend which socioeconomic factors of rural properties and families’ perception were determinant for the intention to restore Polylepis forests in the Central Andes region of Peru. Material and Methods: We collected data through visits and the application of questionnaires. We selected 13 rural communities in the Tulumayo River Basin. We randomly sampled 10 to 20 families in each community, depending on its size, totaling 200 families. We used generalized linear mixed model (GLMM) to test which variables affect the intention to restore the forest. Results: When crops are the main source of income in the property, the families have more intention to restore Polylepis areas, on the other hand, when Polylepis forests are an important source of products for the family subsistence, the intention to restore forests reduces, indicating that higher technological status has a positive impact on restoration. The perception that Polylepis forests are important for the existence of water sources had a positive impact on the families’ intention to restore the areas. However, the perception that Polylepis forests are important for native flora persistence had a negative impact on the intention to restore their areas. Conclusions: Our results showed that investment in improving the productivity of the properties and in the education of their landowners should increase the success of eventual programs for restoration of Polylepis forests.



Sign in / Sign up

Export Citation Format

Share Document