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The Au'au Channel between the islands of Maui and Lanai, Hawaii comprises critical breeding habitat for humpback whales (Megaptera novaeangliae) of the Central North Pacific stock. However, like many regions where marine mega-fauna gather, these waters are also the focus of a flourishing local eco-tourism and whale watching industry. Our aim was to establish current trends in habitat preference in female-calf humpback whale pairs within this region, focusing specifically on the busy, eastern portions of the channel. We used an equally-spaced zigzag transect survey design, compiled our results in a GIS model to identify spatial trends and calculated Neu's Indices to quantify levels of habitat use. Our study revealed that while mysticete female-calf pairs on breeding grounds typically favor shallow, inshore waters, female-calf pairs in the Au'au Channel avoided shallow waters (<20 m) and regions within 2 km of the shoreline. Preferred regions for female-calf pairs comprised water depths between 40–60 m, regions of rugged bottom topography and regions that lay between 4 and 6 km from a small boat harbor (Lahaina Harbor) that fell within the study area. In contrast to other humpback whale breeding grounds, there was only minimal evidence of typical patterns of stratification or segregation according to group composition. A review of habitat use by maternal females across Hawaiian waters indicates that maternal habitat choice varies between localities within the Hawaiian Islands, suggesting that maternal females alter their use of habitat according to locally varying pressures. This ability to respond to varying environments may be the key that allows wildlife species to persist in regions where human activity and critical habitat overlap.

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The ontogeny of behavior in young offspring is a key component of a species life history, influencing short-term survival and life-long future fitness. In this study, we examine the behavioral ontogeny of humpback whale calves during their natal season on the winter breeding grounds. Behavioral data were collected during focal follows for 69 calves. Their relative age was estimated based on the degree of unfurling of the dorsal fin, and analysis of their time budgets revealed that behavior changed as the calves matured. Among the youngest group of calves (n = 27), persistent travel accounted for median 85% (interquartile range 34%) of the calves' time budget, they spent little time alone at the surface and the breathing regime included frequent intermittent breaths. Within the oldest group of calves (n = 26), time spent traveling dropped to a median 47% (IQR 42%) of the time budget, they spent more time at rest, surfaced alone more frequently, and the breathing regime more closely resembled that of adult humpbacks. We suggest potential functions for these and other components of calf behavior during this period, and review our findings in light of recent discussions on the role of predation pressure as a driving force in mysticete migration.

A bioassay to examine the foraging behaviour of the aphidophagous hoverfly, Episyrphus balteatus was used in which various stimuli purported to influence flower choice were tested using model flowers. In choice experiments, E. balteatus exhibited enhanced behavioural responses to the colour yellow, as previously seen in Eristalis by several workers. Previous suggestions that the generalist forager E. balteatus has no preference for colour are re‐examined in the light of this new evidence. The other advertisement cue tested, size, was also demonstrated to play an important role in determining foraging behaviour, with the smaller artificial flowers seemingly preferred. Of the rewards tested, E. balteatus showed preference for the greatest nectar concentrations, whilst increasing pollen did not affect behaviour. These bioassays provided an opportunity to isolate the individual components of decision‐making by E. balteatus during foraging. The separation of sexes and ages in these experiments permitted analysis of inter‐sexual and inter‐generation differences in behaviour, a factor apparently not investigated in previous work.

Summary1 The spatial and temporal variations in aphidophagous syrphid abundance were recorded over two seasons in wildflower resource patches sown in a winter barley crop and associated field margins. Standard census techniques and sticky board trapping were used to assess numbers of syrphids, whilst weekly flower head counts were used to quantify the floral resources available in each of the patches.2 The field margin supported a greater diversity and density of syrphids than the within‐crop wildflower patches, despite having a relatively lower flower head density. Presumably this was in response to other resources that field margins offer, namely additional aphid resources, shelter from predation, lekking sites and suitable flight‐paths.3 The commonest species of syrphid, Episyrphus balteatus, demonstrated a very positive habitat association with the field margin and was rarely reported in the field patches. Therefore, it may be an unsuitable candidate for the biological control of aphids via augmentation of numbers using non‐host resources.4 Patch size and shape had little effect on the spatial distributions of syrphids, probably because of the adult syrphids' high mobility.5 Of greater influence was the number of flowers contained in each habitat patch. Typically, patches with higher numbers of flowers had significantly greater aggregations of hoverflies. Habitat manipulation by the provision of flowers in patches seems to increase the local density of hoverflies. Further work is necessary to establish the importance of flower density in enhancing the control of pest populations.

Flooding is a major problem that reduces soybean [Glycine max (L.) Merr.] growth and grain yield in many areas of the USA and the world. Our objective was to identify the plant and soil characteristics associated with different flooding durations in six fields in central Ohio. The soybean plants were at the V2 and V3 stages when rainfall‐induced flooding occurred. The outer perimeters of the flooded areas were mapped, using GPS (global positioning system) technology, several times during the flooding event to delineate the change of the flooded area over time. Two 9‐m wide transects across the flooded area within each field were divided into plots of 9 m by 9 m according to flooding duration: no flooding, 1 to 3 d, 4 to 6 d, and 6 to 8 d. Soil and plant nutrient levels, grain yield data and grain protein and oil content were determined for each plot. The soil cation‐exchange capacity (CEC), pH, P, Ca, Mn, and Zn concentrations had significant positive correlation with flooding duration. There was a significant negative correlation of flooding duration with the population, height, number of pods, and yield of soybean. There was no significant correlation of flooding duration with seed weight, oil, or protein content of the seeds. Leaf tissue Ca, Mg, B, Fe, Cu, and Al concentrations had a significant positive correlation with flooding duration, whereas leaf tissue N concentration had a significant negative correlation with flooding duration.

While most mammals have whiskers, some tactile specialistsmainly small, nocturnal, and arboreal species-can actively move their whiskers in a symmetrical, cyclic movement called whisking. Whisking enables mammals to rapidly, tactually scan their environment to efficiently guide locomotion and foraging in complex habitats. The muscle architecture that enables whisking is preserved from marsupials to primates, prompting researchers to suggest that a common ancestor might have had moveable whiskers. Studying the evolution of whisker touch sensing is difficult, and we suggest that measuring an aspect of skull morphology that correlates with whisking would enable comparisons between extinct and extant mammals. We find that whisking mammals have larger infraorbital foramen (IOF) areas, which indicates larger infraorbital nerves and an increase in sensory acuity. While this relationship is quite variable and IOF area cannot be used to solely predict the presence of whisking, whisking mammals all have large IOF areas. Generally, this pattern holds true regardless of an animal's substrate preferences or activity patterns. Data from fossil mammals and ancestral character state reconstruction and tracing techniques for extant mammals suggest that whisking is not the ancestral state for therian mammals. Instead, whisking appears to have evolved independently as many as seven times across the clades Marsupialia, Afrosoricida, Eulipotyphla, and Rodentia, with Xenarthra the only placental superordinal clade lacking whisking species. However, the term whisking only captures symmetrical and rhythmic movements of the whiskers, rather than all possible whisker movements, and early mammals may still have had moveable whiskers. Anat Rec, 303:89-99, 2020.