Foraging behavior of parasitoid chalcid to the essential oil from bark of Populus pseudo-simonii P. nigra and Quadraspidiotus gigas

采用四臂式嗅觉仪测定了长棒四节蚜小蜂（Pteroptrix longgiclava(Girault)(Hymenoptera:Aphelinidae))和黄胸扑虱蚜小蜂（Encarsia gigas(Tshumakova)(Hymenoptera:Aphelinidae)),对健康的小青×黑杨（Populus pseudo-simonii×P.nigra)树皮、被杨圆蚧（Quadraspidiotus gigas(Thiem & Gerneck)）危害的杨树皮、杨圆蚧1齿固定若虫的虫体和介壳的挥发油的趋性反应。测定结果表明：被杨圆蚧危害后的小青×黑杨树皮和杨圆蚧1龄因定若虫的介壳对长棒四节蚜小蜂和黄胸扑虱蚜小蜂成虫具有较大的吸引力。3－7μL介壳挥发油和5－9μL受害杨树皮挥发油对长棒四节蚜小蜂的寄主搜寻行为具有较强的引导作用。虫体的挥发油对小蜂的寄生定位也起到了一定的引诱作用。两种小蜂对健康树皮的挥发油几乎没有反应。图4表1参20。

Foraging behavior of the Eurasian Three-toed Woodpecker subspecies Picoides tridactylus funebris in southern Gansu, China

The Three-toed Woodpecker subspecies Picoides tridactylus funebris is endemic to the Qinghai-Tibet plateau in China. No part of its life history was ever reported since its discovery in 1870. To close this gap, we observed foraging behavior of a pair between April and August 2007. A total of 117 observations (28 for male and 89 for female) were obtained by following the birds within their home-ranges using radio-tracking. P. t. funebris preferred foraging on live spruces and snags bigger than available with an average diameter of breast height (DBH) of 32.7 ± 9.2 cm. The most frequent foraging technique was pecking (39.8% of foraging time) and peeling (13.2%). Moreover, sap-sucking was observed more often in P. t. funebris than in P. t. alpinus, suggesting that P. t. funebris was more dependent on the tree sap than the other subspecies. We found distinct niche partitioning between the sexes with respect to use of three out of four investigated parameters of the foraging substrates. These differences were likely related to sexual dimorphism pronounced by slightly larger bill of the male. We concluded that the subspecies P. t. funebris displayed foraging behavior which was very similar to that of other subspecies of the Three-toed Woodpecker.

Shifts in foraging behavior of wintering Hooded Cranes(Grus monacha) in three different habitats at Shengjin Lake, China

Background: Wetland loss and degradation result in a reduction in the availability and quality of food for wintering waterbirds. Birds normally modify their foraging behavior to adapt to variations in food availability. In this study, we compared shifts in foraging behavior of Hooded Cranes(Grus monacha) in three different habitats at Shengjin Lake, China to understand the response of these cranes to changes in habitat.Methods: We investigated the food density and foraging behavior of Hooded Cranes in Shengjin Lake National Nature Reserve from November 2014 to April 2015. We used regression equations to describe the changes in food density. A total of 397 behavioral observations were used in the analyses of their foraging efforts. We fitted a candidate set of generalized mixed linear models to analyze the relationship of foraging efforts and food density. We used a method of information theory to guide the selection of the model and Akaike's Information Criterion to calculate the value of each model. The relationship between food density, disturbances and foraging behavior was illustrated using a generalized linear model.Results: Along with the temporal variation and exploitation of food biomass, the food density varied widely among foraging sites. During the early winter period, foraging efforts were more pronounced in the paddy fields and meadows but not significantly different among the three habitats. The cranes spent more foraging effort in the paddy fields and meadows during the middle stage and in the meadows and mudflats during the late winter. The results of the generalized linear model showed that food density and disturbances had different effects on the rate of foraging success during the winter, while the effect of foraging effort was not significant. Furthermore, the rate of feeding success was markedly affected by disturbances in the paddy fields. The combined action of food density and disturbances had a significant effect on the rate of foraging success in the meadows, while the effect of foraging effort was also not significant in three habitats.Conclusions: Changes in foraging behavior were significant in three habitats, which were affected by food density and disturbances. The rate of foraging success increased in the habitat with low food density and low disturbances to increase the foraging efficiency in the lake. With abundant food and a high level of disturbance, the rate of foraging success decreased to ensure more secure access to food.

Distributional and behavioral responses of the wintering Oriental Storks to drought in China’s largest freshwater lake

Extreme droughts are increasing in frequency and severity globally as a result of climate change.Developing understanding of species’responses to drought is crucial for their conservation,especially in regions experi-encing increased aridity.Although numerous studies have investigated birds’responses to drought,the emphasis has primarily been on landbirds.Drought can significantly alter the wetland environments that waterbirds inhabit,but the response of waterbirds to drought remains understudied.In this study,we surveyed the distri-bution and behavior of Oriental Storks(Ciconia boyciana)in Poyang Lake,which is the largest freshwater lake in China.Results indicate that drought-induced catchment areas at the lowest water level limited the total popu-lation size of Oriental Storks in the sub-lakes.Sub-lakes with large catchment areas at the lowest water level demonstrated a capacity to support a larger population of wintering Oriental Storks.Over time,Oriental Storks exhibited a gradual concentration in Changhu Lake,characterized by larger catchments,after resource depletion in sub-lakes with smaller catchments.Additionally,the duration of Oriental Storks’vigilance and moving be-haviors decreased significantly compared with that observed before the drought.After the drought,Oriental Storks increased their foraging efforts,as evidenced by increased presence in deeper water and reaching their heads and necks into deeper water to forage,higher search rates,but lower foraging rates.In accordance with area-restricted search theory,reductions in habitat quality resulting from drought,including extensive fish die-offs,forced Oriental Storks to increase their foraging efforts.Sustaining a specific water area in sub-lakes during droughts can preserve resource availability,which is crucial for the conservation of Oriental Storks.Imple-menting measures such as water level control and micro-modification of lake bottoms in sub-lakes might mitigate the impact of drought on the piscivorous Oriental Storks.

The influence of past experience on wasp choice related to foraging behavior

Memory has been little studied in social wasps. Vespula germanica （Fab.） （Hymenoptera： Vespidae） frequently revisits nondepleted food sources, making several trips between the resource and the nest. In this study, we analyzed this relocating behavior in order to evaluate whether this species is capable of remembering an established association after 1 h. To this end, we trained wasps to feed from a certain array. Then it was removed, setting it up again 1 h later, but this time 2 baited feeders were put in place, one at the original feeding site and the other opposite the first. We recorded the proportion of returning foragers, and their choice of feeder, after either 1 or 4 feeding trials. After 1 h, 78% of wasps trained with 4 feeding trials and 65% trained with 1, returned to the experimental area. Furthermore, during the testing phase, wasps trained with 4 feeding trials collected food from the previously learned feeder significantly more frequently than from the nonlearned one （P 〈 0.05）. In contrast, wasps that had been trained only once chose both feeders equally. Thus, memory retrieval could be observed 1 h after wasps had collected food on 4 consecutive occasions, but not after only 1. To our knowledge, this is the first study showing that V. germanica is capable of remembering an association 1 h after the last associative event, demonstrating that 1 h does not impair memory retention if4 feeding experiences have occurred.

Long-term spatial memory in Vespula germanica social wasps： the influence of past experience on foraging behavior

Social insects exhibit complex learning and memory mechanisms while for- aging. Vespula germanica （Fab.） （Hymenoptera： Vespidae） is an invasive social wasp that frequently forages on undepleted food sources, making several flights between the resource and the nest. Previous studies have shown that during this relocating behavior, wasps learn to associate food with a certain site, and can recall this association 1 h later. In this work, we evaluated whether this wasp species is capable of retrieving an established association after 24 h. For this purpose, we trained free flying individuals to collect proteinaceous food from an experimental plate （feeder） located in an experimental array. A total of 150 individuals were allowed 2, 4, or 8 visits. After the training phase, the array was re- moved and set up again 24 h later, but this time a second baited plate was placed opposite to the first. After 24 h we recorded the rate of wasps that returned to the experimental area and those which collected food from the previously learned feeding station or the nonlearned one. During the testing phase, we observed that a low rate of wasps trained with 2 collecting visits returned to the experimental area （22%）, whereas the rate of returning wasps trained with 4 or 8 collecting visits was higher （51% and 41%, respectively）. Moreover, wasps trained with 8 feeding visits collected food from the previously learned feeding station at a higher rate than those that did from the nonlearned one. In contrast, wasps trained 2 or 4 times chose both feeding stations at a similar rate. Thus, significantly more wasps returned to the previously learned feeding station after 8 repeated foraging flights but not after only 2 or 4 visits. This is the first report that demonstrates the existence of long-term spatial memory in V. germanica wasps.

A short note on extractive foraging behavior in gray snub-nosed monkeys

Extractive foraging(EF)involves the exploitation of hidden or embedded foods,generally any food that is not visible to the naked eye.Therefore,EF is particularly important for survival in marginal habitats as it provides seasonal fallback foods in low food availability seasons.Although many studies consider primates’EF behavior and category,colobine species are usually categorized as non-extractive foragers and few studies quantitatively examine their EF behavior.In this study,we examined the EF behavior of one colobine species,the gray snub-nosed monkey(Rhinopithecus brelichi),at Yangaoping in Fanjingshan National Nature Reserve,Guizhou.We recorded 6 categories of EF behaviors.The most frequently sought-out foods were seeds,young bamboo and invertebrates.Extracted foods accounted for an average of 26.02%of feeding records.As the monkey engages in little EF behavior in the winter when the food availability is low,these results seem to do not support the hypothesis that EF serves to secure additional resources during lean times in marginal or seasonal habitats.According to these findings,we suggest R.brelich should be considered as an extractive forager.Our study also highlights the need for increased representation of colobines in the EF literature to better inform the discussion concerning its link to primate brain evolution.

Foraging behavior of Chleuastochoerus(Suidae, Artiodactyla): A case study of skull and mandible morpho-functional analysis

The skull and mandible of a Late Miocene fossil pig,Chleuastochoerus,are compared morphologically with those of extant pigs and peccaries,and subjected to a functional analysis.The presence of a rostral bone in the skull and relatively strong rostral muscles indicates that Chleuastochoerus possessed considerable digging ability,though the relatively narrow occipital surface and the shortness of the skull would have restricted the range of motion through which the skull could be swung.The distinctive pre-zygomatic plate and over-canine arch-niche may have played a role in protecting the skull and canines during digging.The massive masticatory muscles,reconstructed based on well-developed parietal and zygomatic crests,would have enabled the mouth to close quickly and contributed to moving the mandible both longitudinally and laterally.The configuration of the cranio-mandibular joint and its relatively high position show clearly that Chleuastochoerus was capable of both crushing and grinding movements during mastication.The comparatively simple structure of the crown surfaces of the cheek teeth suggests that the food of Chleuastochoerus may have been softer than that of extant suids.The diet of Chleuastochoerus is postulated to fall between those of true forest pigs and open habitat pigs,and the habitat of Chleuastochoerus to be relatively humid forest edge or nearby areas of open steppe.

Effects of elevated CO2 on the foraging behavior of cotton bollworm, Helicoverpa armigera

Effects of elevated CO2 on the foraging behavior of cotton bollworm Helicoverpa arrnigera Hübner reared on milky grains of spring wheat grown in ambient, 550μL/L and 750μL/L CO2 concentration atmospheres in open-top chambers （OTC） were studied. The results indicated that： （i） elevated CO2 significantly affected both the type and amount of food eaten by H.arrnigera reared on milky grains of ambient CO2-grown wheat were significant higher than those for bollworm larvae reared on wheat grains grown in 550 and 750μL/L CO2 atmospheres; （ii） when bollworm larvae were reared on mixed milky grains from different CO2-grown wheat （food-choice condition）, larval duration increased significantly-pupal weight, adult longevity, and fecundity decreased significantly, comparing with those reared on milky grains of ambient CO2-grown wheat, 550μL/L CO2-grown wheat and 750μL/L CO2-grown wheat respectively; （iii） significant decreases in the contents of fructose and gross protein （GP） and significant increases in the contents of glucose, amylose, total saccharides （TSC）, TSC： GP ratio, free amino acids and soluble protein in the wheat grains with CO2 rising; （iv） and selected-foraging amount/food-choice index of cotton bollworm H.armigera were significantly positive correlated with the contents of fructose and GP of wheat grains, but they had significantly negative relationships with the contents of glucose, amylose, TSC and TSC： GP ratio of wheat grains.

Effect of conspecific and heterospecific urine odors on the foraging behavior of the golden spiny mouse

The common spiny mouse(Acomys cahirinus)inhibits the foraging activity of the golden spiny mouse(A.russatus).These two sympatric species of spiny mice,which are considered habitat competitors,occur in extreme arid environments.To test this theory of competition,the influence of urinary odors of both conspecific and heterospecific mice on the foraging behavior of A.russatus was studied under controlled laboratory conditions.Twenty adult males,born in captivity and unfamiliar to the odors of the donor mice,were tested in 3 experimental conditions choosing between 2 seed patches that were scented with urine of either heterospecifics(A.cahirinus),conspecifics(A.russatus)or controls(odors of the tested individual).Of the 20 males,12 were also tested with urine of unfamiliar gerbils,bushy-tailed jird,considered as competitors in the field.Both conspecific and heterospecific urine samples from Acomys significantly reduced foraging behavior of A.russatus when compared to the control odor.The inhibitory effect of the Acomys urine does not result from the novelty of chemical stimuli of the urine because no effect was shown with unfamiliar gerbil urine.The findings are in accordance with the general theory that A.cahirinus dominates the foraging activity of A.russatus.We hypothesize that chemical cues in the urine of Acomys spp.might induce a negative effect on the foraging behavior of A.russatus.

The bottlenose dolphin Tursiops truncatus foraging around a fish farm:Effects of prey abundance on dolphins' behavior

The extent to which prey abundance influences both bottlenose dolphin foraging behavior and group size in the presence of human activities has not previously been studied.The primary aim of this study was to identify and quantify how wild bottlenose dolphins respond,individually and as groups,to the relative abundance of prey around a fish farm.Detailed views of dolphins' behavior were obtained by focal following individual animals whilst simultaneously collecting surface and underwater behavioral data.A total of 2150 dive intervals were analyzed,corresponding to 342 focal samples,lasting over 34 hours.Bottlenose dolphins remained submerged for a mean duration of 46.4 seconds and a maximum of 249 seconds.This study provides the first quantified data on bottlenose dolphin diving behavior in a marine fin-fish farm area.This study's results indicate that within a fish farm area used intensively by bottlenose dolphins for feeding,dolphins did not modify dive duration.Additionally,underwater observations confirmed that dolphins find it easier to exploit a concentrated food source and it appears that hunting tactic and not group size plays an important role during feeding activities.Thus,bottlenose dolphins appear capable of modifying their hunting tactics according to the abundance of prey.When top predators display behavioral responses to activities not directed at them,the task of studying all possible effects of human activities can become even more challenging.

Scaly-sided Merganser(Mergus squamatus)equalizes foraging costs with depth by switching foraging tactics

Throughout evolutionary history,animals are finely tuned to adjust their behaviors corresponding to environmental variations.Behavioral flexibility represents an important component of a species'adaptive capacity in the face of rapid anthropogenetic environmental change,and knowledge of animal behaviors is increasingly recognized in conservation biology.In aquatic ecosystem,variation of water depth is a key factor affecting the availability of food;thus,the foraging behaviors of many waterbirds,especially piscivores.In this study,we compared the foraging behaviors of the Scaly-sided Merganser(Mergus squamatus),an endangered migratory diving duck endemic to East Asia,in habitats with different water depths(Shallow waters:0–40 cm;Deep waters:40–300 cm),using video camera records obtained from the known wintering sites during three winters from 2018 to 2020.Further,the energy expenditure of foraging behavior profile and energy intake based on fish sizes were calculated to study the foraging energetics.In total,200 effective video footages that contained 1086 min with 17,995 behaviors and 163 events of catching fish were recorded.Results showed that:1)time length for fishing(including eye-submerging,head-dipping,diving and food handling)of M.squamatus in shallow waters was significantly more than in deep waters;2)M.squamatuss spent significantly more time for preparing(including vigilance,preening and swimming)in deep waters than in shallow waters;3)the mean catch rate was 0.28 fish/min in shallow waters,which is significantly higher than the value of 0.13 fish/min in deep waters;4)despite the distinct foraging behavior profiles and energy intakes,M.squamatus showed similar energetics in shallow and deep waters.We concluded that M.squamatus is a good example of behavioral flexibility that aligns with expectations of optimal foraging theory,in that it behaves in accordance to resource availability in different environments,resulting in high foraging efficiency.

Mobile robot path planning based on adaptive bacterial foraging algorithm

The utilization of biomimicry of bacterial foraging strategy was considered to develop an adaptive control strategy for mobile robot, and a bacterial foraging approach was proposed for robot path planning. In the proposed model, robot that mimics the behavior of bacteria is able to determine an optimal collision-free path between a start and a target point in the environment surrounded by obstacles. In the simulation, two test scenarios of static environment with different number obstacles were adopted to evaluate the performance of the proposed method. Simulation results show that the robot which reflects the bacterial foraging behavior can adapt to complex environments in the planned trajectories with both satisfactory accuracy and stability.

Effects of UV-B radiation on fitness related behaviors of the sea urchin Strongylocentrotus intermedius

Ozone depletion induced by anthropogenic gases has been increasing the transmission of solar ultraviolet-B radiation(UV-B, 280–315 nm) through the atmosphere, which may impact the fitness of marine invertebrates in intertidal and shallow waters. To our knowledge, however, the responses of fitness related behaviors to UV-B radiation at different intensities have been rarely studied in marine invertebrates. For the first time, the present study investigated the eff ects of exposure of one hour to UV-B radiation at different intensities on foraging behavior, Aristotle's lantern reflex and righting behavior of the sea urchin Strongylocentrotus intermedius. Exposure of one hour to UV-B radiation at 10 μW/cm^2 significantly reduced foraging behavior. An intensity dependent eff ect of exposure to UV-B radiation was found in the duration of the Aristotle's lantern reflex. Exposure to UV-B radiation at 20 μW/cm^2 for one hour significantly reduced the duration of the Aristotle's lantern reflex, but 10 μW/cm^2 did not. There was no significant diff erence of righting response time among sea urchins exposed to 0, 10 and 20 μW/cm^2 for one hour. To test potential carryover ef fects, the behavioral traits were re-measured three days later. We found significant carryover eff ects of UV-B radiation on foraging time and righting response time, but not on the duration of the Aristotle's lantern reflex. The present study indicates that a brief exposure of one hour to UV-B radiation can significantly aff ect the duration of Aristotle's lantern reflex, righting response time and foraging behavior of a sea urchin, although the immediate impacts and carryover eff ects were highly trait dependent. This study provides new information into the behavioral responses of marine invertebrates to exposure to UV-B radiation. Future studies should be carried out to investigate long-term carryover eff ects of UV-B radiation on behavioral and physiological fitness related traits.

Foraging areas of Rousettus leschenaulti on the Hainan Island of China

We investigated the foraging area of three individuals (1 female and 2 males) of Rousettus leschenaulti (Chiroptera,Pteropodidae) in suburban Haikou City, Hainan Province, South China from November 2005 to January 2006 using radio telemetry.These animals left the daytime roosting sites about 90 min after sunset with no significant difference in departure time betweenthe male and female bats. The average active times were 391.8 min for males and 533.7 min for the female, respectively.By reconstructing 93 radio-telemetry recording positions, we found that the long axis of foraging area of the bats ranged from7.45 to 11.70 km. The foraging area of the female (3867 ha) was larger than that of the males (1138 ha), and there was overlapbetween the foraging areas of different individuals. These bats usually kept the same flight routes across a few successive daysfrom the daytime roosting site to the foraging areas. Our findings suggested that female R. leschenaulti may explore a larger foragingarea than males. No obvious territorial behaviors were observed in our studied area.

Nutrition Analysis of Forage Plants and Foragnig Behavior of Mongolian Gazella

The study on winter food constitution of Mongolian gazella (Procapra gutturosa) was conducted in Hulunbeir grassland(Xinbarhuyou Banner, Hulunbeir League, Inner Mongolia) from spring 1994 to summer 1995. With microhistological analysis technique of feces, 21 plant species were identified to be availlable for Mongolian gazella as forage in winter and their nutritive trait were analyzed. Some foraging behavior of Mongolian gazella were also discribed.

Effect of Light Intensity and Nutrient Availability on Clonal Growth and Clonal Morphology of the Stoloniferous Herb Halerpestes ruthenica

In a greenhouse experiment plasticity of clonal growth and clonal morphology of the stoloniferous rosette herb Halerpestes nahenica Ovcz. in response to differing levels of light intensity and nutrient availability was studied. Total plant dry weight, leaf area of primary ramets, total number of ramets and of stolons, and total stolon length were significantly reduced, while specific internode length and specific petiole length significantly increased under deep shading (6.25% of high light intensity, 5.3% of full daylight) or under low nutrient availability. Under low nutrient availability, mean stolon internode length of H. ruthenica was significantly larger while branching intensity and number of ramets smaller than those under high nutrient availability. These responses are consistent with the foraging model of clonal plants, indicating that H. nahenica is able to forage nutrients through the plastic responses of clonal growth and clonal. morphology when it grows in heterogeneous environments. However, under deep shading, both mean stolon internode length and mean petiole length were significantly reduced, which disagrees with the findings of many other stoloniferous herbs in response to low or medium levels of shading (ca. 13%-75% of high light intensity, >10% of full daylight), suggesting that under deep shading stoloniferous herbs may not forage light through the plastic responses of spacer length. Many traits such as total plant dry weight, total number and length of stolons, total length of secondary and tertiary stolons. total number of ramets, leaf area of primary ramets and branching intensity were markedly influenced by the interaction effect of light intensity and nutrient availability. Under high light intensity nutrient availability affected these traits more pronouncedly, however under low light intensity nutrient availability either did not affect or affected less markedly on these traits, indicating that fight intensity had significant effect on nutrient foraging in H. nahenica. Under deep shading or low nutrient availability, H. ruthenica may increase its mean stolon internode length by means of thinning stolon internodes (i.e., an increase in specific internode length), which provides it with more chance to escape from resource-poor sites.

Wintering ecology of the Black Stork (Ciconia nigra) in Beijing

The Black Stork (Ciconia nigra) is a new winter resident in Beijing due to temperature changes.To understand the wintering ecology of this species better, a field survey covering the number of birds of this population, habitat selection, feeding activity and grouping behavior was conducted at the Shidu Nature Reserve from January 2004 to March 2009. The results show that the Black Stork selected the Juma River at this nature reserve as their new winter habitat. The number of birds in this population decreased from 28 in the 2004/2005 winter to 17 in the 2007/2008 winter with a subsequent recovery to 23 the following year. The wintering flock was formed in mid-November and dispersed in mid-March, but the date changed with seasonal temperature fluctuations. The storks exhibited feeding habitat fidelity and the main food type was fish (＞ 92.4%). There was no significant variation in food composition between adults and sub-adults (Mann-Whitney U test, U = 1.00, p = 0.44). Feeding activity occurred in the morning and at noon during early winter, but concentrated in the afternoon during mid winter, divided into dawn and dusk in late winter. Daily fish intake was 538 g for adults and 449 g for sub-adults if the period of foraging reached six hours in the wild, which was similar to the level under artificial feeding. Agonistic behavior among feeding birds was observed among group members in late winter. The main negative factor for wintering Black Stork was a reduced feeding habitat resulting from increased water depth due to damming of the river to benefit tourism and to wetland exploitation.

Activity Recording of Free-Ranging Tri-spine Horseshoe Crabs in the Southeastern Coast of Sabah,Borneo

In Inderasabah(southeast Sabah),tri-spine horseshoe crab Tachypleus tridentatus was observed for their locomotion activity using data loggers from September to November in 2015.A female with acceleration and depth-temperature loggers and five males with acceleration loggers were recaptured between 10 and 49 days after their release.From the record of 194 activity days that involve all six T.tridentatus,four horseshoe crabs,including the female,were active throughout the 24.0 h cycle,whereas the activity of the remaining two males was consistent with the 12.4 h cycle.Using the 40-day recording,three horseshoe crabs,including the female,were primarily active around the new moon and full moon,but they were dormant around the first and third quarter moon days.The female spent much time in shallow shores(depth<0.3 m)during the new moon and full moon.This result indicated that the female attempted to spawn in a minimum of three spring tide periods while lingering in the vicinity.Meanwhile,after spawning,the female spent time foraging in shallow water(depth 0.3–18 m).As for the two male individuals,their activity was consistent with semi-lunar periodicity.Therefore,both of them were in amplexus.In addition,a solitary male individual was active only during the first and third quarter moon days.Through activity recording,all the T.tridentatus in Inderasabah was active during daytime and nighttime.This result was contrary to T.tridentatus activity cycles in western Japan,where the species was found to be primarily nocturnal.Perhaps,the regional differences in activity cycles for T.tridentatus were related to their population adaptation toward water temperature,depth,and prey-searching periods.

Gone with the wind： Seasonal trends in foraging movement directions for a central-place forager

Lesser kestrels Falco naumanni are migratory central-place foragers that breed in dynamic arable landscapes. After arriving from migration, kestrels have no knowledge of the distribution of crops, and consequently prey, around their colony. The energy demand of pairs increases as breeding season progresses, but at the same time prey abundance, and their knowledge on prey distribution, also increases. Wind can have a strong influence on flight cost and kestrels should try to reduce energy expendi- ture when possible. When prey abundance is low, kestrels have little knowledge of prey distribution, and pairs have no chicks, they could reduce foraging flight cost by leaving the colony with tailwinds. When prey is abundant, knowledge on prey distribu- tion has increased, and chick demand is high, kestrels should fly to the most favorable foraging patches. We analyzed foraging trips directions in a lesser kestrel colony along the breeding season and in relation to wind speed and direction. We recorded 664 foraging trips from 19 individuals using GPS-dataloggers. We found that outward flights direction changed from uniform to a concentrated distribution along the season, as prey abundance and individual experience increased. We also found a temporal trend in the angular difference between outward flights and wind directions, with low values early in the season and then increa- sing as expected, but again low values at the end, contrary to expectation. Results suggest changes in kestrels foraging strategy along the season in relation to wind. Kestrels depart more with tailwinds in exploratory flights early in the season, while there is a spurious coincidence in direction to preferred foraging patches and dominant wind direction at the end [Current Zoology 60 （5）： 604-615, 2014].