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1.
Front Nutr ; 9: 1008577, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386947

RESUMO

Hedonic measurements in the frame of consumer tests of foods are prone to many different biases and the validity of test designs has been subject to much research with special emphasis on the role of context. While bringing elements of natural consumption context to the testing conditions is generally seen as an improvement, other aspects of the test design such as the task format have received little attention. In particular, the influence of analytical questions on hedonic responses has been studied in standardized contexts only. This study aimed to assess whether synthetic and analytical evaluation tasks result in different hedonic responses when the test is conducted in a natural consumption context. Bread and pizzas with different degrees of culinary preparation (homemade, readymade, and a combination of the two) were tested on three separate days in a university cafeteria. Overall liking scores of the bread and the three different pizzas were obtained either with a synthetic (hedonic question only) or with an analytical task (hedonic question plus intensity attributes). Care was taken to avoid any other changes to normal eating conditions, notably by recruiting on the spot only those customers who had spontaneously chosen pizza as part of their lunch. Liking scores of the homemade pizza were lower with the analytical task while the scores of the other two pizzas did not change significantly. Moreover, different rankings of the pizzas were obtained when the data were analyzed separately for each evaluation task format. The synthetic evaluation task would have led to the conclusion that the homemade pizza was the best liked and the readymade being the least liked, while the analytical evaluation task would have led to the conclusion that the "mixed" pizza would be liked significantly more than the other two. The effect of the task format (i.e., lower scores with the analytical task) was more pronounced when participants reported they had spent more time in the queue. These results strengthen the view that the task is part of the evaluation context and must be carefully considered when one wishes to design ecologically valid consumer tests.

2.
Front Nutr ; 8: 749596, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35141262

RESUMO

Consuming too much fat, sugar, and salt is associated with adverse health outcomes. Food reformulation is one possible strategy to enhance the food environment by improving the nutritional quality of commercial products. However, food reformulation faces many hindrances. One way to alleviate some of these hindrances is to embrace a multicriteria approach that is based on a market inventory. In this objective, additional sensory screening and water content analyses allow going beyond nutrition and composition information on the packaging. However, due to feasibility reasons for later in-depth analyses, it is necessary to work with several reduced and manageable products. To the best of the authors' knowledge, in the literature, there is no sample selection approach taking into account multiple criteria as a base for future food reformulation. The overall aim of this paper is to propose a method to select the best representative products from the market base, for future reformulation by going beyond nutrition and composition information on the packaging. This approach considered therefore nutrition, composition, economic, water content, and sensory information with the example of the cookies market. The first step is the creation of an extensive cookie database including sensory and water content information. In total 178 cookies among the French market were identified, then focus was placed on 62 chocolate chip cookies only. Sensory screening and water content analyses of all 62 products were conducted. The second step is to make an informed subset selection, thanks to a cluster analysis based on 11 nutrition, composition, and water content variables. A representative subset of 18 cookies could be derived from the obtained clusters. The representativity was evaluated with statistical uni- and multivariate analyses. Results showed a broad variety of chocolate chips cookies with a large nutritional, compositional, water content, and sensory differences. These results highlighted the first paths for future reformulation in this product category and showed the importance to include physical product information beyond the information on the packaging. This complete database on the selected cookies constituted a solid base for identifying future reformulation levers, in order to improve the nutritional quality and health.

3.
JASA Express Lett ; 1(5): 051201, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-36154109

RESUMO

Passive acoustic monitoring (PAM) can inform wildlife management by providing information on the distribution of cetaceans. This paper presents an automatic data selection for validation (ADSV) method to effectively identify all species acoustically present in large PAM data sets. The ADSV method involves the application of automated detectors, the automated selection of a portion of data for manual review, and the evaluation/optimization of automated detectors. Using an exemplar data set, results from the ADSV method were compared to a more intensive systematic manual review method. The two methods were found to have similar species occurrence results (hourly occurrence matching 73%-100%).


Assuntos
Acústica , Cetáceos , Animais
4.
Glob Chang Biol ; 26(9): 4812-4840, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32450009

RESUMO

Six baleen whale species are found in the temperate western North Atlantic Ocean, with limited information existing on the distribution and movement patterns for most. There is mounting evidence of distributional shifts in many species, including marine mammals, likely because of climate-driven changes in ocean temperature and circulation. Previous acoustic studies examined the occurrence of minke (Balaenoptera acutorostrata) and North Atlantic right whales (NARW; Eubalaena glacialis). This study assesses the acoustic presence of humpback (Megaptera novaeangliae), sei (B. borealis), fin (B. physalus), and blue whales (B. musculus) over a decade, based on daily detections of their vocalizations. Data collected from 2004 to 2014 on 281 bottom-mounted recorders, totaling 35,033 days, were processed using automated detection software and screened for each species' presence. A published study on NARW acoustics revealed significant changes in occurrence patterns between the periods of 2004-2010 and 2011-2014; therefore, these same time periods were examined here. All four species were present from the Southeast United States to Greenland; humpback whales were also present in the Caribbean. All species occurred throughout all regions in the winter, suggesting that baleen whales are widely distributed during these months. Each of the species showed significant changes in acoustic occurrence after 2010. Similar to NARWs, sei whales had higher acoustic occurrence in mid-Atlantic regions after 2010. Fin, blue, and sei whales were more frequently detected in the northern latitudes of the study area after 2010. Despite this general northward shift, all four species were detected less on the Scotian Shelf area after 2010, matching documented shifts in prey availability in this region. A decade of acoustic observations have shown important distributional changes over the range of baleen whales, mirroring known climatic shifts and identifying new habitats that will require further protection from anthropogenic threats like fixed fishing gear, shipping, and noise pollution.


Assuntos
Acústica , Animais , Oceano Atlântico , Região do Caribe , Groenlândia , Sudeste dos Estados Unidos
5.
Appetite ; 142: 104345, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31276709

RESUMO

Meat consumption in Western countries is declining and, while the proportion of strict vegetarians remains low, intermediate diets such as flexitarianism have been developing in recent years. Our objectives were to identify the different levels of transition towards low-meat diets, characterize how these diets differ in terms of food intake, and identify whether attitudes and beliefs can explain these degrees of transition. In a representative survey of the French adult population conducted in 2018 (n = 2055), participants declared whether they followed a particular diet and completed a food frequency questionnaire on 29 food sources of protein and a questionnaire on their attitudes and beliefs regarding protein sources. We identified four dietary types based on these declarative data: vegetarians, flexitarians, pro-flexitarians and omnivores. The theory of planned behavior was used to predict meat intake and intentions to reduce meat intake. The sample contained 2.5% vegetarians, 6.3% flexitarians, 18.2% pro-flexitarians and 72.9% omnivores. The diet groups displayed specific dietary profiles and attitudinal scores. Compared with omnivores, pro-flexitarians consumed less red meat, more vegetables and legumes and were much more in agreement about the environmental impacts of meat. Compared with pro-flexitarians, flexitarians consumed less red meat and processed meat, and agreed much more about the health impacts of meat. Finally, versus flexitarians, vegetarians consumed almost no meat but far more legumes, nuts and seeds, and were much more sensitive to animal welfare issues. Attitudes, social norms and perceived behavioral control (PBC) predicted intentions to reduce meat consumption but attitude was the most important predictor. Intentions and PBC were both predictive of meat consumption. The dietary type related to the level of meat intake could be predicted by self-declared attitudes and beliefs regarding protein sources.


Assuntos
Dieta , Proteínas Alimentares , Conhecimentos, Atitudes e Prática em Saúde , Carne , Adolescente , Adulto , Idoso , Dieta Saudável , Feminino , França/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Sobrepeso/epidemiologia , Tamanho da Porção , Fatores Sexuais , Fatores Socioeconômicos , Inquéritos e Questionários , Vegetarianos , Adulto Jovem
6.
Nutrients ; 11(7)2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295831

RESUMO

Promoting a more balanced animal/plant dietary protein ratio by changing portion sizes or introducing new foods is a promising means to improve diet quality, but little is known about the willingness of individuals to adopt such changes. Our objective was to assess the willingness to adopt dietary changes by these means. In a French cross-sectional study in 2018 (n = 2055), we analyzed the association between the willingness to eat smaller or larger portions or to introduce non-consumed protein foods and the current dietary patterns of individuals and their socio-demographic characteristics. These modifications had previously been identified as improving the nutrient adequacy of diets. Participants were more willing to eat smaller portion sizes than to introduce new foods and to eat larger portion sizes. The willingness for any modification varied depending on the food groups concerned. Participants were also more willing to eat larger portions and less willing to eat smaller portions when they were the most frequent consumers of the foods concerned. Participants were more willing to eat a new food if it was consumed in large quantities by individuals with a similar dietary pattern. This study underlines the importance of accounting for individual food habits when issuing nutritional recommendations.


Assuntos
Dieta/estatística & dados numéricos , Proteínas Alimentares , Comportamento Alimentar/fisiologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Tamanho da Porção , Adolescente , Adulto , Estudos Transversais , Inquéritos sobre Dietas , Feminino , França/epidemiologia , Comportamentos Relacionados com a Saúde/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Ecol Evol ; 9(7): 4231-4244, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31016001

RESUMO

Estimates of abundance and survivorship provide quantifiable measures to monitor populations and to define and understand their conservation status. This study investigated changes in abundance and survival rates of fin whales (Balaenoptera physalus) in the northern Gulf of St. Lawrence in the context of anthropogenic pressures and changing environmental conditions. A long-term data set, consisting of 35 years of photo-identification surveys and comprising more than 5,000 identifications of 507 individuals, formed the basis of this mark-recapture study. Based on model selection using corrected Akaike Information Criterion, the most parsimonious Cormack-Jolly-Seber model included a linear temporal trend in noncalf apparent survival rates with a sharp decline in the last 5 years of the study and a median survival rate of 0.946 (95% confidence interval (CI) 0.910-0.967). To account for capture heterogeneity due to divergent patterns of site fidelity, agglomerative hierarchical cluster analysis was employed to categorize individuals based on their annual and survey site fidelity indices. However, the negative trend in survivorship remained and was corroborated by a significant decline in the estimated super-population size from 335 (95% CI 321-348) individuals in 2004-2010 to 291 (95% CI 270-312) individuals in 2010-2016. Concurrently, a negative trend was estimated in recruitment to the population, supported by a sharp decrease in the number of observed calves. Ship strikes and changes in prey availability are potential drivers of the observed decline in fin whale abundance. The combination of clustering methods with mark-recapture represents a flexible way to investigate the effects of site fidelity on demographic variables and is broadly applicable to other individual-based studies.

8.
J Sci Food Agric ; 99(8): 3983-3991, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30719740

RESUMO

BACKGROUND: Consumers are being encouraged to increase the proportion of plant protein in their diet to tend to a sustainable food system. Solutions could include developing a food rich in plant protein. However, these new products have an interest only if they are in accordance with expectation and the liking of consumers. In this context, extruded snack balls were developed to explore the sensory drivers of liking and barriers to consumption of formulated products with a high level of plant proteins. Eight different products varying in the type of cereal flour (rice or wheat) and pea flour content (from 60% to 90%) were developed following a factorial design. Eighty omnivore and 72 flexitarian consumers were recruited to evaluate the liking of these products. In addition, their sensory properties were described by a trained panel according to a profile method. RESULTS: The cereal type had globally more influence on liking than the percentage of pea. However, liking was inversely correlated with pea flour content, regardless of the cereal type. The main drivers of liking are texture criteria (in particular crispy and puffy), whereas flavor perception (pea, green) constitutes a barrier to acceptance. Interestingly, very few differences of liking were observed depending on the diet of consumers even though the attitudes of flexitarian'towards such type of products differed from those of omnivores. We identified three clusters of consumers based on their preferences. Pea flavor acceptance or rejection could explain these clusters. Although most consumers rejected pea flavor, approximately 40% of the participants preferred the products with highest pea content. CONCLUSION: The results of the present study will help provide guidance for innovative plant food design and formulation. © 2019 Society of Chemical Industry.


Assuntos
Comportamento do Consumidor , Proteínas de Plantas/metabolismo , Lanches/psicologia , Adulto , Cor , Feminino , Aromatizantes/química , Aromatizantes/metabolismo , Manipulação de Alimentos , Humanos , Masculino , Oryza/química , Oryza/metabolismo , Pisum sativum/química , Pisum sativum/metabolismo , Proteínas de Plantas/química , Paladar , Triticum/química , Triticum/metabolismo
9.
Appetite ; 131: 160-168, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30172680

RESUMO

In adults, fat is a major determinant of food palatability. From the onset of complementary feeding (CF) adding fat to complementary foods is recommended to ensure an optimal growth and cognitive development. However, whether adding fat to complementary foods would impact acceptance (in terms of intake and liking) has been little investigated. This study sought 1) to evaluate acceptance of added fat (either vegetable oils or dairy fat) in a vegetable puree in weaning-age infants; 2) to determine whether early differential fat exposure through milk (breast milk and formula have different fat composition) and fat addition in complementary foods can influence acceptance and 3) to explore if fat acceptance can be related to inter-individual differences in salivary compounds potentially involved in fat perception. Twenty six infants with contrasted milk feeding history participated and were introduced with complementary foods at 4.8 months. During the 1st month of complementary feeding, acceptance of 3 broccoli purees (0% fat, 7% of vegetable oils, 7% of dairy fat) was determined through ad libitum intake and global liking, in the laboratory and at home. Saliva was collected: lipolytic activity and carbonic anhydrase 6 concentration were determined. Puree intakes were not impacted by fat addition, whatever the type of added fat. Moreover, the history of milk feeding (breast milk vs. vegetable oils based formulas) in the very first months did not explain acceptance for added fat. Finally, no links between intake and saliva composition were evidenced. Altogether, this study found that the addition of fat did not modify food acceptance by infants during early complementary feeding. Thus, future research should investigate the development of fat acceptance over experience in early infancy.


Assuntos
Gorduras na Dieta/administração & dosagem , Preferências Alimentares , Fenômenos Fisiológicos da Nutrição do Lactente , Saliva/química , Feminino , Humanos , Lactente , Alimentos Infantis , Masculino , Verduras
10.
PLoS One ; 13(6): e0199431, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29928009

RESUMO

Little is known of the spatio-temporal occurrence of beaked whales off western Ireland, limiting the ability of Regulators to implement appropriate management and conservation measures. To address this knowledge gap, static acoustic monitoring was carried out using eight fixed bottom-mounted autonomous acoustic recorders: four from May to December 2015 on Ireland's northern slope and four from March to November 2016 on the western and southern slopes. Recorders ran for 205 to 230 days, resulting in 4.09 TB of data sampled at 250 kHz which could capture beaked whale acoustic signals. Zero-crossing-based automated detectors identified beaked whale clicks. A sample of detections was manually validated to evaluate and optimize detector performance. Analysis confirmed the occurrence of Sowerby's and Cuvier's beaked whales and Northern bottlenose whales. Northern bottlenose whale clicks occurred in late summer and autumn, but were too few to allow further analysis. Cuvier's and Sowerby's clicks occurred at all stations throughout the monitoring period. There was a significant effect of month and station (latitude) on the mean daily number of click detections for both species. Cuvier's clicks were more abundant at lower latitudes while Sowerby's were greater at higher latitudes, particularly in the spring, suggesting a spatial segregation between species, possibly driven by prey preference. Cuvier's occurrence increased in late autumn 2015 off northwest Porcupine Bank, a region of higher relative occurrence for each species. Seismic airgun shots, with daily sound exposure levels as high as 175 dB re 1 µPa2·s, did not appear to impact the mean daily number of Cuvier's or Sowerby's beaked whale click detections. This work provides insight into the significance of Irish waters for beaked whales and highlights the importance of using acoustics for beaked whale monitoring.


Assuntos
Acústica , Processamento de Sinais Assistido por Computador , Análise Espaço-Temporal , Vocalização Animal/fisiologia , Baleias/fisiologia , Acústica/instrumentação , Animais , Oceano Atlântico , Ritmo Circadiano/fisiologia , Geografia , Irlanda , Fatores de Tempo , Análise de Ondaletas
11.
J Acoust Soc Am ; 143(4): EL285, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29716304

RESUMO

The echolocation signals of most beaked whale species are still unknown. In fact, out of the 22 species comprising the family Ziphiidae, only the echolocation pulses for 7 species have been clearly described. This study describes two distinct beaked whale echolocation signals recorded in the Cook Strait region using passive acoustic technology. These signals differ from previously described Ziphiid species clicks. A description of the time-frequency characteristics of the two signals is provided. Understanding the characteristics of these signals is necessary to correctly identify species from their echolocation signals and enables future monitoring of beaked whales using passive acoustics techniques.


Assuntos
Acústica , Ecolocação/fisiologia , Vocalização Animal/fisiologia , Baleias/fisiologia , Animais , Nova Zelândia , Especificidade da Espécie , Fatores de Tempo , Baleias/classificação
12.
Sci Rep ; 7(1): 13460, 2017 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-29044130

RESUMO

Given new distribution patterns of the endangered North Atlantic right whale (NARW; Eubalaena glacialis) population in recent years, an improved understanding of spatio-temporal movements are imperative for the conservation of this species. While so far visual data have provided most information on NARW movements, passive acoustic monitoring (PAM) was used in this study in order to better capture year-round NARW presence. This project used PAM data from 2004 to 2014 collected by 19 organizations throughout the western North Atlantic Ocean. Overall, data from 324 recorders (35,600 days) were processed and analyzed using a classification and detection system. Results highlight almost year-round habitat use of the western North Atlantic Ocean, with a decrease in detections in waters off Cape Hatteras, North Carolina in summer and fall. Data collected post 2010 showed an increased NARW presence in the mid-Atlantic region and a simultaneous decrease in the northern Gulf of Maine. In addition, NARWs were widely distributed across most regions throughout winter months. This study demonstrates that a large-scale analysis of PAM data provides significant value to understanding and tracking shifts in large whale movements over long time scales.


Assuntos
Acústica , Baleias , Animais , Oceano Atlântico , Geografia , Dinâmica Populacional , Análise Espacial
13.
Appetite ; 99: 277-284, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26826527

RESUMO

In France, 50% of consumers sweeten plain yogurts prior to consumption. This study measured how much sugar consumers added under contextualized testing conditions. Participants (199 French adults who regularly consume plain yogurt adding sugar) were given a plain yogurt (125 g) at the end of a full meal and were allowed to sweeten it with their usual sweetener (caster sugar, honey, or jam). The quantities added were measured indirectly by weighing the sweetener containers before and after use; they were then converted into equivalent quantities of sucrose, or "added sugar." Participants were asked to describe their relative hunger, thirst, and liking for plain yogurt and to estimate the quantity of sweetener they had added. On average, participants added 13.6 g of sugar to their yogurts, which is higher than the 10.2 g of sugar contained in pre-sweetened commercial yogurts (125 g). More sugar was added when subjects used jam (24.4 g/yogurt, n = 36) as opposed to caster sugar (11.0 g/yogurt, n = 134) or honey (12.1 g/yogurt, n = 29). Age, socio-professional category, and BMI had a significant influence on added-sugar quantity. Based on behavior and attitude, participants could be separated into three evenly sized groups: "low sugar users" (n = 67, median = 6.1 g/yogurt), who tended to control their food intake, "medium sugar users" (n = 66, median = 11.4 g/yogurt), and "heavy sugar users" (n = 66, median = 19.9 g/yogurt) who sought immediate satisfaction. To our knowledge, this study is the first to provide robust data on the amount of sugar consumers add to plain yogurts in contextualized conditions (self preparation during a real meal). Our findings show that consumers underestimated by half the quantity of sweetener they added.


Assuntos
Comportamento do Consumidor , Comportamento Alimentar , Adoçantes Calóricos/análise , Autorrelato , Iogurte/análise , Adolescente , Adulto , Idoso , Índice de Massa Corporal , Feminino , Análise de Alimentos , França , Humanos , Masculino , Pessoa de Meia-Idade , Adoçantes Calóricos/administração & dosagem , Adulto Jovem
14.
Appetite ; 104: 44-51, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-26606886

RESUMO

Several authors showed that providing choice may increase food liking and food intake. However, the impact of choice may be modulated by assortment's characteristics, such as the number of alternatives or their dissimilarity. The present study compared the impact of choice on food liking and intake under the two following conditions: (1) when choosing a product to consume from among similar products versus dissimilar products; and (2) when choosing a product to consume from among pleasant products versus unpleasant products. Two experiments were carried out using the same design: the "apple puree" experiment (n = 80), where the volunteers choose from among similar products (apple purees varying in texture) and the "dessert" experiment (n = 80), where the volunteers choose from among dissimilar products (fruit dessert, dairy dessert, custard, pudding). During the first session, participants rated their liking for 12 products (apples purees or desserts). Then the participants were divided into a "pleasant" group (n = 40) in which volunteers were assigned three pleasant products, and an "unpleasant" group (n = 40) in which volunteers were assigned three unpleasant products. Finally, all of the volunteers participated in a choice session - volunteers were presented with their three assigned products and asked to choose one of the products, and a no-choice session - volunteers were served with one product that was randomly selected from among their three assigned products. Providing choice led to an increase in food liking in both experiments and an increase in food intake only for the desserts, namely only when the volunteers chose the product to consume from among "not too similar" alternatives. No effect of assortment's pleasantness was observed.


Assuntos
Comportamento de Escolha , Comportamento do Consumidor , Ingestão de Alimentos/psicologia , Preferências Alimentares/psicologia , Abastecimento de Alimentos/métodos , Adolescente , Adulto , Afeto , Feminino , Humanos , Masculino , Prazer , Adulto Jovem
15.
Appetite ; 90: 160-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25796209

RESUMO

Consumption of a product is preceded by an anticipation of its qualities by the consumer, which can itself modify the consumption experience. Improved knowledge of anticipation would allow better manipulation of it, for example to enhance the acceptance of healthier foods. According to the Assimilation-Contrast theory, the size of anticipation-reality divergence determines how anticipation influences consumers' satisfaction. For small divergences, experienced pleasure is the same as the anticipated pleasure (Assimilation); for large ones, the effect of surprise provokes an even larger discordance with that which was anticipated (Contrast). Few studies have attempted to observe both effects simultaneously, or to consider the anticipation-reality divergence quantitatively rather than qualitatively; these were the study's objectives. A range of 10 flavored drinks was developed to vary progressively in intensity. Ninety healthy young men consumed samples during two separate sessions. In session 1, hedonic and sensory scores of all drinks were recorded during blind tasting. In session 2, three drinks were chosen as references for taste intensity, and associated with neutral symbols that served as labels. Subjects then consumed 36 drink samples, each one bearing a label. For half of the samples drinks did not correspond to labels, creating a range of anticipation-reality divergence. By predicting session 2 scores using linear modeling with session 1 blind ratings as input, it was confirmed that both Assimilation and Contrast effects on hedonic ratings were present (Assimilation (t(89) = 5.645, p < 0.0001) and Contrast (t(89) = 3.186, p = 0.002 or t(89) = 2.494, p = 0.015, depending on the drink-label combination)). This study was the first to position Assimilation and Contrast within a quantitative context using controlled divergence variation rather than products from distinct categories.


Assuntos
Antecipação Psicológica , Bebidas , Comportamento do Consumidor , Alimentos , Prazer , Percepção Gustatória/fisiologia , Adulto , Humanos , Modelos Lineares , Masculino , Paladar/fisiologia , Adulto Jovem
16.
PLoS One ; 10(3): e0121374, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25785462

RESUMO

Global warming poses particular challenges to migratory species, which face changes to the multiple environments occupied during migration. For many species, the timing of migration between summer and winter grounds and also within-season movements are crucial to maximise exploitation of temporarily abundant prey resources in feeding areas, themselves adapting to the warming planet. We investigated the temporal variation in the occurrence of fin (Balaenoptera physalus) and humpback whales (Megaptera novaeangliae) in a North Atlantic summer feeding ground, the Gulf of St. Lawrence (Canada), from 1984 to 2010 using a long-term study of individually identifiable animals. These two sympatric species both shifted their date of arrival at a previously undocumented rate of more than 1 day per year earlier over the study period thus maintaining the approximate 2-week difference in arrival of the two species and enabling the maintenance of temporal niche separation. However, the departure date of both species also shifted earlier but at different rates resulting in increasing temporal overlap over the study period indicating that this separation may be starting to erode. Our analysis revealed that the trend in arrival was strongly related to earlier ice break-up and rising sea surface temperature, likely triggering earlier primary production. The observed changes in phenology in response to ocean warming are a remarkable example of phenotypic plasticity and may partly explain how baleen whales were able to survive a number of changes in climate over the last several million years. However, it is questionable whether the observed rate of change in timing can be maintained. Substantial modification to the distribution or annual life cycle of these species might be required to keep up with the ongoing warming of the oceans.


Assuntos
Adaptação Fisiológica , Migração Animal , Jubarte/fisiologia , Movimento , Oceanos e Mares , Estações do Ano , Temperatura , Animais , Aquecimento Global , Inquéritos e Questionários
17.
J Acoust Soc Am ; 126(6): 3319-28, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20000946

RESUMO

This paper reports on the acoustic detection of bowhead whale (Balaena mysticetus) songs from the Bering-Chukchi-Beaufort stock, including the first recordings of songs in the fall and early winter. Bowhead whale songs were detected almost continuously in the Chukchi Sea between October 30, 2007 and January 1, 2008 and twice from April 16 to May 5, 2008 during a long-term deployment of five acoustic recorders moored off Point Lay and Wainwright, AK, between October 21, 2007 and August 3, 2008. Two complex and four simple songs were detected. The complex songs consisted of highly stereotyped sequences of four units. The simple songs were primarily made of sequences of two to three moan types whose repetition patterns were constant over short periods but more variable over time. Multiple song types were recorded simultaneously and there is evidence of synchronized song variation over time. The implications of the spatiotemporal distribution of song detection with respect to the migratory and mating behavior of western Arctic bowheads are discussed.


Assuntos
Baleia Franca , Vocalização Animal , Acústica , Animais , Regiões Árticas , Eletrônica , Meio Ambiente , Gelo , Oceanos e Mares , Estações do Ano , Espectrografia do Som , Fatores de Tempo
18.
J Acoust Soc Am ; 125(3): 1774-82, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19275334

RESUMO

Passive acoustic data are increasingly being used as a tool for helping to define marine mammal populations and stocks. Fin whale (Balaenoptera physalus) songs present a unique opportunity to determine interstock differences. Their highly stereotyped interpulse interval has been shown to vary between geographic areas and to remain stable over time in some areas. In this study the structure of songs recorded at two geographically close feeding aggregations in the Gulf of St. Lawrence (GSL) and Gulf of Maine (GoM) was compared. Recordings were made from September 2005 through February 2006 in the GSL and intermittently between January 2006 and September 2007 at two locations in the GoM. 6257 pulse intervals corresponding to 19 GSL and 29 GoM songs were measured to characterize songs from both areas. Classification trees showed that GSL songs differ significantly from those in the GoM. The results are consistent with those derived from other stock structure assessment methodologies, such as chemical signature and photoidentification analysis, suggesting that fin whales in these areas may form separate management stocks. Song structure analysis could therefore provide a useful and cost-efficient tool for defining conservation units over temporal and geographical scales relevant to management objectives in fin whales.


Assuntos
Vocalização Animal , Animais , Baleia Comum , Geografia
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