Foraging Rate Research Articles

Reef effect of vertical relief on the shelter-seeking and foraging processes of juvenile fat greenling (Hexagrammos otakii) in a mesocosm experiment

Artificial reefs with sufficient vertical relief can support secondary fish production by attracting pelagic fishes and/or providing both shelter and food resources for them. Although vertical relief is a widely investigated factor in reef design, little is known about how the shelter-seeking and foraging processes of benthic fishes respond to relief changes. With a laboratory mesocosm experiment using hollow blocks to construct different combinations of reef volume and relief, we tested the effect of vertical relief of artificial reefs on a benthic juvenile fish (fat greenling, Hexagrammos otakii). The volume of the experimental reef depended on the number of blocks, and the reef relief was changed by the stacking pattern of the blocks at each volume. We measured the aggregation, sheltering, and foraging effects of each reef structure, respectively, based on fish distribution around the reef, their shelter-seeking behavior under disturbance, and their foraging rate. Our results demonstrate that increasing the vertical relief while maintaining the reef volume had a positive effect on the aggregating juvenile fat greenling but decreased the sheltering effect of the reef. The relationship between the foraging effect and relief was nonlinear, and high relief would also limit the foraging rate of juvenile fat greenling. We suggest that a reef needs to have sufficient relief to provide habitat for juvenile fat greenling, as well as sufficient horizontal cover to shelter the fish during a disturbance. Not only limited resources (e.g., food and shelter) but also the shelter-seeking and foraging processes of the benthic fish could have a potential impact on secondary production. Our findings highlight the importance of considering the aggregation, sheltering, and foraging effects of relief on benthic fishes in the field observation and the design of artificial reefs.

No evidence of predator odor avoidance in a North American bird community

Recent advances in our understanding of avian chemical communication have highlighted the importance of olfaction in many aspects of avian life. Prior studies investigating predator avoidance behaviors in response to predator odor cues have produced mixed results across species and contexts. Here we assess if a community of birds in Eastern Pennsylvania displays avoidance behaviors towards predator odor cues in a natural foraging setting. We use clay caterpillars to measure foraging activity by birds in the presence of predator (bobcat) urine, non-predator (rabbit) urine, and water controls in two different environmental contexts (field vs. forest). Although we detected a weak trend for birds to forage less at predator urine-treated sites, we found no significant difference in avian foraging between the site types. We did find that foraging rates between environmental contexts changed significantly over the course of the experiment, with forest sites showing decreasing foraging rates and field sites showing increasing foraging rates. Our results reinforce the published literature that avoidance of predator odors by birds may not be ubiquitous across contexts and species.

Low foraging rates drive large insectivorous bats away from urban areas

AbstractUrbanization has significant impacts on wildlife and ecosystems and acts as an environmental filter excluding certain species from local ecological communities. Specifically, it may be challenging for some animals to find enough food in urban environments to achieve a positive energy balance. Because urban environments favor small‐sized bats with low energy requirements, we hypothesized that common noctules (Nyctalus noctula) acquire food at a slower rate and rely less on conspecifics to find prey in urban than in rural environments due to a low food abundance and predictable distribution of insects in urban environments. To address this, we estimated prey sizes and measured prey capture rates, foraging efforts, and the presence of conspecifics during hunting of 22 common noctule bats equipped with sensor loggers in an urban and rural environment. Even though common noctule bats hunted similar‐sized prey in both environments, urban bats captured prey at a lower rate (mean: 2.4 vs. 6.3 prey attacks/min), and a lower total amount of prey (mean: 179 vs. 377 prey attacks/foraging bout) than conspecifics from rural environments. Consequently, the energy expended to capture prey was higher for common noctules in urban than in rural environments. In line with our prediction, urban bats relied less on group hunting, likely because group hunting was unnecessary in an environment where the spatial distribution of prey insects is predictable, for example, in parks or around floodlights. While acknowledging the limitations of a small sample size and low number of spatial replicates, our study suggests that scarce food resources may make urban habitats unfavorable for large bat species with higher energy requirements compared to smaller bat species. In conclusion, a lower food intake may displace larger species from urban areas making habitats with high insect biomass production key for protecting large bat species in urban environments.

Phylogenetic variation in raw cow milk microbiota and the impact of forage combinations and use of silage inoculants.

The microbiota of bulk tank raw milk is known to be closely related to that of microbial niches of the on-farm environment. Preserved forage types are partof this ecosystem and previous studies have shown variations in their microbial ecology. However, little is known of the microbiota of forage ration combinations and the transfer rates of associated species to milk. We identified raw milk bacteria that may originate from forage rations encompassing either hay (H) or grass/legume silage uninoculated (GL) as the only forage type, or a combination of GL and corn silage uninoculated (GLC), or grass/legume and corn silage both inoculated (GLICI). Forage and milk samples collected in the fall and spring from 24 dairy farms were analyzed using 16S rRNA gene high-throughput sequencing following a treatment with propidium monoazide to account for viable cells. Three community types separating H, GL, and GLICI forage were identified. While the H community was co-dominated by Enterobacteriaceae, Microbacteriaceae, Beijerinckiaceae, and Sphingomonadaceae, the GL and GLICI communities showed high proportions of Leuconostocaceae and Acetobacteraceae, respectively. Most of the GLC and GLICI rations were similar, suggesting that in the mixed forage rations involving grass/legume and corn silage, the addition of inoculant in one or both types of feed does not considerably change the microbiota. Raw milk samples were not grouped in the same way, as the GLC milk was phylogenetically different from that of GLICI across sampling periods. Raw milk communities, including the GLICI group for which cows were fed inoculated forage, were differentiated by Enterobacteriaceae and other Proteobacteria, instead of by lactic acid bacteria. Of the 113 amplicon sequence variants (ASVs) shared between forage rations and corresponding raw milk, bacterial transfer rates were estimated at 18 to 31%. Silage-based forage rations, particularly those including corn, share more ASVs with raw milk produced on corresponding farms compared to that observed in the milk from cows fed hay. These results show the relevance of cow forage rations as sources of bacteria that contaminate milk and serve to advance our knowledge of on-farm raw milk contamination.

Agricultural grasslands provide forage for honey bees but only when nearby

Knowledge of foraging currencies and costs is important for understanding honeybee food collection economics and to parameterize their foraging behaviors as indicators of habitat quality, which is important in the identification of management targets in human-altered landscapes. Previous research has yielded inconsistent results regarding the relationship between honey bees and important agroecosystems, such as agricultural grasslands. Waggle dance decoding provides a method for resolving these inconsistencies by mapping and quantifying bee recruitment to agricultural grasslands using statistical methods that appropriately account for foraging distance, or cost. Here we decoded 3881 dances across two foraging years to investigate when and where honey bees forage in a mixed-use landscape in Virginia, with a particular interest in honey bee use of agricultural grasslands (pastures and haylands). We initially observe that bees recruited heavily to agricultural grasslands compared to croplands, developed lands and forests, where the percent foraging to that land type was at 30.7% (CI: 29.4–31.8%), and thus significantly higher than its representation in the landscape (c. 23%). Honey bees also recruited heavily to agricultural grasslands across months, with percent foraging ranging from 26.9% (23.5–30.1%) in August to 38.8% (31.3–46.9%) in October. However, when we examined distance-corrected foraging rates, which allowed us to compare land type attractiveness when flight cost is removed, we found that the agricultural grasslands were not more attractive than the broader landscape and were significantly less attractive than, for example, croplands. We additionally identify potential forage gaps in agricultural grasslands during June and August, while also distinguishing them as a possible source of forage in October before colony overwintering in this landscape. Furthermore, we qualitatively observe a hot spot, demonstrating high foraging interest that is composed of agricultural grasslands, developed lands, and croplands and is itself a mixed-use area. Together, these results demonstrate that honey bees utilize heterogeneous land areas and underscore the importance of statistical analyses that incorporate biological knowledge. Lastly, these data will be important in informing future management aimed at pollinators in agricultural grasslands.

Nutritional management of equine gastric ulcers

Over the last 10 years there has been increasing awareness and subsequently recorded cases of equine gastric ulcer syndrome and with this comes an increased interest in appropriate nutrition and feed management. This review presents a systematic approach to assessing the ration of a horse at risk of or diagnosed with equine gastric ulcer syndrome and demonstrates the ample evidence upon which to base nutritional recommendations for horses with equine squamous gastric disease, and to a lesser extent, equine glandular gastric disease, with an emphasis on forage. Careful selection and management of the forage ration should be the first step in designing a suitable ration, followed by selection of an appropriately low starch and sugar (less than 2 g per kg body weight per day and 1 g per kg body weight per meal) complementary feed.

Thermal dependence of Daphnia life history reveals asymmetries between key vital rates

Temperature variation affects virtually every aspect of ectotherms' ecological performance, such as their foraging rate, reproduction, and survival. Although these changes influence what happens at higher levels of organizations, such as populations and communities, qualitative changes in dynamics usually require some degree of asymmetry between key vital rates, i.e. that different vital rates, such as growth, development, fecundity and mortality rates, respond differently to temperature. In order to identify possible asymmetries among vital rates and/or life stages, we characterized the thermal response of individuals a clone of Daphnia sinensis, drawn from a high-mountain environment in Taiwan, and examined the temperature dependence of growth, maturation, reproduction, and mortality rates, as well as fitness measures (r and R0) at eight temperatures. Daphnia sinensis was able to maintain reproductive success over a broad range of temperatures, much wider than the one experienced in its environment. However, negative effects of temperature were perceptible at temperatures much lower than the highest one at which they can achieve reproductive success. Adult mortality greatly increased for temperatures above 23 °C, and other vital rates started to decelerate, resulting in a large drop in lifetime reproductive success. This finding implies that D. sinensis may be able to persist over a wide range of temperatures, but also that it may become more sensitive to the detrimental effect of species interactions at increased temperatures. Different vital rates responded relatively similarly at low temperatures, but the degree of asymmetry among these rates was much more pronounced at higher temperatures. In particular, rates associated with adult performance decelerated more strongly than juveniles’ rates. These findings indicate that elevated temperatures affect the balance between juvenile and adult performance, which is known to have a crucial role in Daphnia population dynamics. We discuss the implications of these results for the dynamics of structured populations.

Abundance, foraging behavior and pollination efficiency of insects visiting the flowers of Aonla (Emblica officinalis)

Many insect species visit the flowers of a plant and play an important role in their pollination. Of late, the interest of the pollination biologists has been to determine their relative contribution towards the reproductive success of the plant. Such information is lacking on the pollinators of Aonla (Emblica officinalis Gaertn.), a plant of very high nutritive and medicinal importance. Therefore, let’s attempt to make this study to generate such information on this plant. The study was conducted on three varieties of Aonla (viz. Chakaiya, NA-7 and NA-10) for two years. An entire range of flower visitors of this fruit plant was captured with hand net from its field during its flowering period and were identified. On the basis of foraging mode, the flower visitors were characterized as pollinators and non-pollinators. Their abundances, foraging rates, activity durations and number of pollen grains carried on the surface were recorded, and these parameters were used to determine their relative contribution towards the reproductive success of this plant. Among the 12 insect species visiting the flowers of Aonla at the study site, 5 belonged to Hymenoptera, 6 to Diptera and one to Lepidoptera. Apis dorsata was the most abundant visitor having maximal foraging rate and carried maximal number of loose pollen grains, followed by A. mellifera, A. florea and Sarcophaga sp; other visitors had lesser values of these parameters. On the basis of these parameters, melittophilous mode of pollination was found to predominate in Aonla. However, the plant was found to be benefitted from the multispecies pollinator guild, and the pollinator diversity seemed to matter for maximization of pollination in Aonla. Therefore, there is a dire need to conserve the pollinator diversity

Leaving more than footprints: Anthropogenic nutrient subsidies to a protected area

AbstractMobile animals that traverse ecosystem boundaries can fundamentally reshape environments by providing critical nutrient and energy inputs to the ecosystems they inhabit. In particular, aggregations of seabirds often transform coastal and island ecosystems through large amounts of nutrient‐rich guano deposition. Anthropogenically driven losses of these subsidies can occur through changes in abundance of mobile species, including seabirds, and have been shown to drive whole‐scale ecosystem state change on islands. However, even though many species that forage on anthropogenic food sources are highly mobile and may thus play important roles in moving nutrients from urban systems to otherwise conserved ecosystems, the impacts of anthropogenic supplements on spatial subsidies have been largely ignored. Here we examine the effects of large nesting colonies of Western Gulls (Larus occidentalis), a generalist carnivore known to forage on human refuse, on the Channel Islands of California. Specifically, we explore how their foraging on human subsidies may change nutrient deposition patterns at their relatively remote and protected breeding islands. We equipped gulls with GPS loggers to assess the frequency of urban foraging, and we partnered this tracking data with bird density data to estimate the rate of wild and urban‐derived guano deposition on two different islands. Consistent with research on other gull species, we found high (up to 40%) but island‐specific rates of urban foraging, resulting between 66 and 93 kg ha−1 of guano in these two sites during the breeding season, a level greater than half the amount of fertilizer applied annually in typical commercial agricultural settings and likely the primary source of nitrogen and phosphorus inputs to this system. Specifically, we estimate that 27 kg ha−1 year−1 of nutrient‐rich guano is shuttled to these otherwise isolated islands from anthropogenic sources. This research highlights the large shadow (i.e., footprint) that human activity can cast on even remote ecosystems by driving significant nutrient enrichment through impacts on animal behavior and connectivity.

PERFORMA PRODUKSI ENTOG (Cairina moschata) JANTAN YANG DIBERI RANSUM BERBASIS HIJAUAN ECENG GONDOK (Eichhornia crasipess)

The performance of mutton is influenced by quality feed, easy to obtain, and does not compete with humans. Water hyacinth has a fairly high content of protein, fiber, fat, and energy. The purpose of this study was to analyze the effect of the use of water hyacinth-based forage rations on the performance of sorghum. The study was conducted experimentally using a completely randomized design (CRD). A total of 80 male mutton were placed in 20 cage plots, so that each cage plot consisted of 4 birds. The types of treatment used were P0 (100% rice bran) as control, P1 (75% rice bran + 25% water hyacinth), P2 (50% rice bran + 50% water hyacinth), P3 (25% rice bran + 75% water hyacinth). The variables observed were ration consumption, body weight gain, ration conversion, feed cost per gain, and mortality. The research data were analyzed using analysis of variance and if they showed significant differences, they were further tested using Duncan's multiple distance test. The results showed that the ration consumption, body weight gain, ration conversion, and feed cost per gain with the addition of water hyacinth in the ration statistically showed a significant difference while the mortality calculated descriptively did not show any difference. Mortality occurred in treatment P3 (25% rice bran + 75% water hyacinth). It can be concluded that in order to improve the performance of male gibbons, the provision of forage water hyacinth in the ration should not be more than 50%.

OPENING UP FORAGE FIELDS DURING THE SNOWY SEASON - AN EFFECTIVE WINTER BIOTECHNICAL TECHNIQUE FOR FEEDING WILD CLOVEN-HOOFED MAMMALS

Despite the technical diversity of techniques for winter feeding of wild ungulates, technologies for opening up forage fields during abnormal periods of the wintering cycle have serious biological potential. In winter, when high snow cover blocks access of ungulates to natural forage in form of fallen leaves and grass rags under snow, clearing biotechnical fields before vegetation becomes exposed is an efficient method of feeding the wintering fauna, especially for Siberian roe deer. By clearing snow from “winter pastures”, where biotech crops and grasses such as sunflowers, oats, peas, and alfalfa were sown, large roe deer groups can be provided with a good and balanced forage ration. Taken together, these biotechnical measures compensate for the lowering of the level of forage resources during winter anomalies and encourage the dynamics of roe deer population growth and the process of reproduction in this species.

Nutritional management of equine gastric ulcers

Over the last 10 years there has been increasing awareness and subsequently recorded cases of equine gastric ulcer syndrome and with this comes an increased interest in appropriate nutrition and feed management. This review presents a systematic approach to assessing the ration of a horse at risk or diagnosed with equine gastric ulcer syndrome and demonstrates the ample evidence upon which to base nutritional recommendations for horses with equine squamous gastric disease, and to a lesser extent, equine glandular gastric disease, with an emphasis on forage. Careful selection and management of the forage ration should be the first step in designing a suitable ration, followed by selection of an appropriately low starch and sugar (less than 2g per kg body weight per day and 1g per kg body weight per meal) complementary feed. There is still more to learn about the role of supplements in the prevention and treatment of equine gastric ulcer syndrome, thus these should currently be viewed as an adjunct to an appropriate base diet and not as an isolated solution.

Daya Suka Kalkun terhadap Hijauan, Dedak Padi dan Ransum Komersial dengan Free Choice Feeding

The purpose of this study was to evaluate the consumption of feed ingredients (forage, rice bran and commercial rations) in adult local turkeys using free choice feeding. A total of seven adult male turkeys were used in this study, fed with forage (Musa paradisiaca, Ipomea spp, and Indigofera sp leaves), rice brand and commercial ration. Five kinds of feed ingredients were placed in different feeders in each turkey cage. The fresh cut forage was prepared into small pieces of 1-2 cm. Each feed ingredient was analyzed for nutrient content (moisture content, crude protein, crude fat, crude fiber, NFE (Nitrogen Free Extract), ash and gross energy). The data obtained were analyzed descriptively. The results showed that the most palatability forage by adult native turkeys was ipomea spp, indigofera spp and Musa paradisiaca leaves respectively. The commercial ration was the most preferred feed ingredient of all the feed ingredients tested and was followed by rice bran. Adult local turkeys consumed fresh forage was 62 % and total rice bran and commercial feeds was 38%, resp. Consumption of dry matter forage was 17.59% and total rice bran and commercial rations was 82.41%. It can be concluded that turkey feed can consist of forage, rice bran and commercial ration.
 Key words: free choice feeding, Indigofera sp, Ipomea sp, Musa paradisiaca, native turkey, rice bran

Ascertaining foraging rate of pollinators in Ricinus communis L. in Haryana, India

Foraging rate of different pollinator species under the genus Apis and non-Apis studied on two castor (Ricinus communis) hybrid under agro-ecological conditions of Haryana, revealed that irrespective of interspecific variation, the maximum foraging rate was found associated with Apis florea followed by A. dorsata, A. cerana and A. mellifera. Further, Eristalnus sp. visits of flowers were the lowest. Adding to the visiting frequency, honey producing bees (Apis sp.) visited significantly more flower per unit time compared to other pollinators (non-Apis) species. The study gave an idea of different foraging rates of different pollinators on castor flower.

Prior exposure to weathered oil influences foraging of an ecologically important saltmarsh resident fish.

Estuarine ecosystem balance typically relies on strong food web interconnectedness dependent on a relatively low number of resident taxa, presenting a potential ecological vulnerability to extreme ecosystem disturbances. Following the Deepwater Horizon (DwH) oil spill disaster of the northern Gulf of Mexico (USA), numerous ecotoxicological studies showed severe species-level impacts of oil exposure on estuarine fish and invertebrates, yet post-spill surveys found little evidence for severe impacts to coastal populations, communities, or food webs. The acknowledgement that several confounding factors may have limited researchers’ abilities to detect negative ecosystem-level impacts following the DwH spill drives the need for direct testing of weathered oil exposure effects on estuarine residents with high trophic connectivity. Here, we describe an experiment that examined the influence of previous exposure to four weathered oil concentrations (control: 0.0 L oil m−2; low: 0.1 L oil m−2; moderate: 0.5–1 L oil m−2; high: 3.0 L oil m−2) on foraging rates of the ecologically important Gulf killifish (Fundulus grandis). Following exposure in oiled saltmarsh mesocosms, killifish were allowed to forage on grass shrimp (Palaeomonetes pugio) for up to 21 h. We found that previous exposure to the high oil treatment reduced killifish foraging rate by ~37% on average, compared with no oil control treatment. Previous exposure to the moderate oil treatment showed highly variable foraging rate responses, while low exposure treatment was similar to unexposed responses. Declining foraging rate responses to previous high weathered oil exposure suggests potential oil spill influence on energy transfer between saltmarsh and off-marsh systems. Additionally, foraging rate variability at the moderate level highlights the large degree of intraspecific variability for this sublethal response and indicates this concentration represents a potential threshold of oil exposure influence on killifish foraging. We also found that consumption of gravid vs non-gravid shrimp was not independent of prior oil exposure concentration, as high oil exposure treatment killifish consumed ~3× more gravid shrimp than expected. Our study findings highlight the sublethal effects of prior oil exposure on foraging abilities of ecologically valuable Gulf killifish at realistic oil exposure levels, suggesting that important trophic transfers of energy to off-marsh systems may have been impacted, at least in the short-term, by shoreline oiling at highly localized scales. This study provides support for further experimental testing of oil exposure effects on sublethal behavioral impacts of ecologically important estuarine species, due to the likelihood that some ecological ramifications of DwH on saltmarshes likely went undetected.

The legacy of predator threat shapes prey foraging behaviour.

Predators exert strong selection on prey foraging behaviour such that prey responses may reflect a combination of ancestral effects of predators (genetic and nongenetic transgenerational effects), past individual experience with predators (phenotypic plasticity), and current exposure to predators (behavioural response). However, the importance of these factors in shaping prey foraging behaviour is not well understood. To test the relative effects of ancestry, prior experience, and current exposure, we measured foraging rates and food size preference of different ancestry and exposure groups of Western mosquitofish in the presence and absence of immediate threat from predatory largemouth bass. Our results confirm that mosquitofish had lower foraging rate in the immediate presence of predator threat. Mosquitofish also foraged at a lower rate if they had ancestry with predators, regardless of immediate threat. In contrast, individual prior experience with predators only caused reduced foraging rates in the immediate presence of a predator. This suggests that phenotypic plasticity could carry a lower risk of maladaptive antipredator responses-i.e., reduced food intake-in the complete absence of a predator. Finally, in the presence of a predator, mosquitofish with both ancestry and experience with predators consumed larger, presumably more energetically valuable, food items. Overall, our results show that non-consumptive effects of predators on prey behaviour can persist within and across generations, such that the legacy of past predator exposure-or "the ghost of predation past"-may continue to shape prey behaviour even when predators are no longer around.

Virulent Disease Epidemics Can Increase Host Density by Depressing Foraging of Hosts.

AbstractAll else equal, parasites that harm host fitness should depress densities of their hosts. However, parasites that alter host traits may increase host density via indirect ecological interactions. Here, we show how depression of foraging rate of infected hosts can produce such a hydra effect. Using a foraging assay, we quantified reduced foraging rates of a zooplankton host infected with a virulent fungal parasite. We then parameterized a dynamical model of hosts, parasites, and resources with this foraging function, showing how foraging depression can create a hydra effect. Mathematically, the hydra arose when increased resource productivity exceeded any increase in resource consumption per host. Therefore, the foraging-mediated hydra effect more likely emerged (1) for hosts that strongly control logistic-like resources and (2) during larger epidemics of moderately virulent parasites. We then analyzed epidemics from 13 fungal epidemics in nature. We found evidence for a foraging-mediated hydra effect: large outbreaks depressed foraging rate and correlated with increased densities of both algal resources and Daphnia hosts. Therefore, depression of the foraging rate of infected hosts can produce higher host densities even during epidemics of parasites that increase host mortality. Such hydras might prevent the collapse of host populations but also could produce higher densities of infected hosts.

319 Predicting Urinary Nitrogen Excretion from Milk Urea Nitrogen of Fresh Forage or Total Mixed Ration Fed Dairy Cows: A Meta-analysis

Abstract Urine nitrogen excretion (g/d; UN) represent a significant environmental impact for both confinement feeding and pastoral based dairy systems. It is difficult to measure UN directly due to animal handling and labor requirements, especially in forage based production systems. The currently available milk urea nitrogen (MUN) equations have been shown to overestimate UN excretion of grazing dairy cows compared with an equation using urinary creatinine and UN concentration, indicating that diet may alter the relationship between MUN and UN. This potential was explored using data retrieved (treatment means: n = 69 and 27 for fresh forage [FF] and total mixed ration [TMR] fed cattle, respectively) from the literature and new data obtained from dairy cows fed FF (n = 15) in metabolism crates was used to test the new equations. The TMR data from literature was further split into a training set (to develop the model; n = 53) and a test set (to validate the model; n = 16). There was an interaction for diet type (P < 0.01) where UN (g/d) = 0.023 × MUN (mg/dL) × live-weight (kg, LW) for TMR fed cattle, (similar to a pre-established equation); however, UN (g/d) = 0.015 × MUN × LW for FF fed cattle. For FF based equations, the New MUN equation and the creatinine equation showed good precision and accuracy (Lin’s CCC = 0.79 and 0.74, respectively) and adequate predictive ability (RMSEP = 29.8 and 35.9, respectively). The new MUN equation for TMR fed cattle showed excellent accuracy and precision (Lin’s CCC = 0.87) with good predictive ability (RMSEP = 24.3) for UN excretion (observed mean = 216.5 g/d). The new equations generated during this meta-analysis provide promising predictive ability of UN excretion, which can be used for management considerations, future research, and policy making.

IslandBased Assemblage Pattern and Foraging Profile of Insect Flower Visitors on Aegialitis rotundifolia -a Near Threatened Mangrove Plant from Indian Sundarban.

Understanding the association pattern and foraging behaviour of flower visitors is crucial to determine their role in the interaction with plants. To analyse the insect flower visitor association as well as their foraging profile on Aegialitis rotundifolia Roxb.-a near threatened mangrove plant, present study has been conducted among four islands of Indian Sundarban for three consecutive years. Results using first three Hill numbers depicted that, the species richness and Shannon and Simpson diversity of flower visitors were higher among the islands situated far from the sea than the islands neighbouring to the sea. NMDS analysis showed moderately ordinate data structure for island-year-based flower visitor association. Furthermore, network analysis for island-based visitor assemblage showed a significantly generalised network with no specialisation among islands. Five abundant visitors were further analysed for foraging profile, where the highest foraging rate was shown by Apis dorsata Fabricius, 1793 and the highest handling time was shown by Micraspis discolor (Fabricius, 1798). Moreover, all the visitors except M. discolor showed a significant variation in their foraging rate among different time frames. Furthermore, only M. discolor showed significant variation in their foraging behaviour when compared individually with each visitor in all the time frames. Present findings conclude that, flower visitors showed a generalised assemblage pattern among islands. Both honey bees provided excellent foraging on this plant and butterflies were good foragers too. Therefore, to device conservation strategies for this plant, protection of flower visitors must be of paramount concern.

Serendipitous observations from animal-borne video loggers reveal synchronous diving and equivalent simultaneous prey capture rates in chinstrap penguins

Seabirds often engage in coordinated, cooperative foraging to improve detection and capture of prey. An extreme example of such coordinated behavior is synchronicity, whereby the movements of individuals are aligned temporally and spatially. Synchronous diving among penguins has been reported, but simultaneous observations of predation by synchronously diving individuals have not. We instrumented chinstrap penguins (Pygoscelis antarcticus) during their incubation period in December 2019 from Cape Shirreff, Livingston Island, Antarctica (60.79°W, 62.46°S) with video and depth recorders to monitor predator foraging behavior and prey consumption rates. Serendipitously, two instrumented individuals, accompanied by a third, banded individual, engaged in synchronous foraging activities on Antarctic krill (Euphausia superba) for 9.25 h. This group formed ashore, transited together to their foraging area, remained in close visual contact after dives, synchronously timed diving behavior, and foraged at similar depths. Prey capture rates were positively correlated across dives and total consumption estimates were equivalent for the two instrumented birds during the video observation period. Video loggers confirmed that synchronous diving and foraging behavior are among the behavioral repertoire of chinstrap penguins and demonstrated equivalent prey capture rates by synchronously foraging predators. The results further suggest that group formation while ashore and group cohesion during a foraging trip may facilitate shared foraging success among group members.