Aggregation Sites Research Articles

Water loss, not overheating, limits the activity period of an endothermic Sonoran Desert bee

Abstract Desert animals must manage the physiological stress caused by heat and desiccation; evaporative heat loss mitigates overheating but exacerbates water stress. Small endothermic flying insects may be particularly vulnerable to overheating and water stress as a result of high surface area to volume ratios, but we lack quantitative understanding of the relative magnitude of these abiotic stressors in flying desert invertebrates, despite their ecological importance. During the hottest and driest weeks of year, many thousands of males of the Sonoran Desert digger bee (Centris caesalpiniae) flew near‐continuously at elevated thorax temperatures for hours at mating aggregation sites, while fighting other males and digging for females. To determine whether incapacitating high temperatures or water loss limited the activity period of male C. caesalpiniae, we assessed wet and dry body mass and water content through the activity period, flight durations using mark–recapture methods, crop volume and sugar content, microclimate selection, water balance during flight, critical water content and maximum critical temperature. Body masses and sizes of males declined through the morning. Body water content scaled isometrically with total body wet mass. Crop volume and sugar content did not vary throughout the day or with bee size. Maximum critical temperature during flight was 51°C for large‐morph C. caesalpiniae males, similar to those measured for other bees, and well above body temperatures reached in the field, suggesting that avoidance of overheating does not limit activity in this desert bee. The critical water content of Centris bees averaged 50%, at the low end of those measured for other bees. Measures of net water loss rate indicated that males approached lethal water loss limits within 4 h, a duration in the range of measured daily flight activity, suggesting that desiccation tolerance limits activity. Remarkably, male C. caesalpiniae were not observed to forage at floral or water sources during the activity period, yet they returned over multiple days, suggesting that these males have a mechanism to rehydrate when not at the mating aggregation. Read the free Plain Language Summary for this article on the Journal blog.

Spawning aggregations of checkered snapper (Lutjanus decussatus) and blackspot snapper (L. fulviflamma): seasonality, lunar-phase periodicity and spatial distribution within spawning ground.

Snappers (family Lutjanidae) are important fisheries target species and some species are known to form spawning aggregations at particular spawning grounds. The present study investigated the ecological characteristics of fish aggregations of two snapper species (checkered snapper Lutjanus decussatus and blackspot snapper L. fulviflamma) that form at a particular site. Specifically, the aims were to clarify (1) seasonality and lunar-phase periodicity of fish aggregation formation, (2) fine-scale spatial distribution of fish density (spatial variations of fish density at intervals of several-tens meters) within the aggregation site, (3) size and age frequency distributions of fishes in the aggregation site, (4) gonad development, (5) to compare fish abundance between inside and outside the aggregation site, and (6) to verify that fish aggregations of the two snapper species were spawning aggregation. Underwater observations using a 600m×5m transect revealed that greater fish abundance of Lutjanus decussatus was found monthly between May and October, and clear positive peaks in the fish abundance were found only around the last-quarter moon. This lunar-related periodicity in the increase of fish abundance was confirmed by a time-series analysis (correlogram). Within the aggregation site, L. decussatus showed a relatively uniform distribution. In contrast, greater fish abundance of L. fulviflamma was found monthly between April and October, and clear positive peaks in the fish abundance were found around the last-quarter moon (April, May, June and October) or new moon (July, August and September). This lunar-related periodicity was also confirmed by correlogram. Lutjanus fulviflamma showed a relatively clumped distribution within the aggregation site. Most females of the two species in the aggregation site had hydrated eggs, indicating that the two species form aggregations for reproduction. The two species, although occurring simultaneously, are considered to form aggregations of conspecifics only. For L. decussatus, average fork length and age of males and females were 229.2 mm and 243.9 mm and 9.4 years and 8.1 years, respectively. For L. fulviflamma, average fork length and age of males and females were 233.9 mm and 246.9 mm and 6.8 years and 8.1 years, respectively. Fish abundance inside the aggregation site was 266.8-fold and 141557.1-fold greater than those outside the aggregation site for L. decussatus and L. fulviflamma, respectively. These results showed that (1) fish aggregation formation of the two snapper species was predictably repeated in particular months and lunar-phase, (2) it was predictably found at the particular site, (3) the fish abundance in the aggregation site markedly exceeded the fish abundance outside the aggregation site, and (4) the two species form aggregations for reproduction. Therefore, it is suggested that the fish aggregations for the two species can be regarded as spawning aggregations.

Occupancy of acoustically tagged oceanic manta rays, Mobula birostris, in Bahia de Banderas, Mexico

The oceanic manta ray (Mobula birostris) is an endangered species commonly seen at oceanic islands and seamounts; however, seasonal aggregations have been described in highly productive, coastal areas. Oceanic manta rays are found in high numbers seasonally in Bahía de Banderas, Mexico, a unique nearshore aggregation site for the species. We used acoustic telemetry to examine the influence of environmental variables on the occurrence of 66 tagged oceanic manta rays over a seven-year period from 2015 to 2021. Seasonal trends in oceanic manta ray occurrence showed a peak in detections from January to March, and another peak from May to early October. Oceanic manta rays were present when the temperature ranged between 25 °C and 29 °C, the southward wind speeds ranged between 3 and 5 m s–1, the westward wind speed between 2.5 and 4.5 m s–1. Furthermore, oceanic manta rays’ presence was higher at high and low tides and when Chlorophyll-a values ranged between 2.5 and 7 mg m3-1. Results also suggest that El Niño Southern Oscillation (ENSO) had a strong effect on oceanic manta ray presence in the bay, which is consistent with previous studies. The detections of oceanic manta rays in the south of the bay, were greater in the morning hours, suggesting that during the night they may move to deeper waters, similar to other reported studies of manta and devil rays. Our model suggested a tag retention time of 300 days. This study serves as a baseline for future management plans for the species to minimize impacts on this population from human activities occurring in close proximity to oceanic manta ray aggregation sites.

APPI-Derived Cyclic Peptide Enhances Aβ42 Aggregation and Reduces Aβ42-Mediated Membrane Destabilization and Cytotoxicity.

An amyloid precursor protein inhibitor (APPI) and amyloid beta 42 (Aβ42) are both subdomains of the human transmembrane amyloid precursor protein (APP). In the brains of patients with Alzheimer's disease (AD), Aβ42 oligomerizes into aggregates of various sizes, with intermediate, low-molecular-weight Aβ42 oligomers currently being held to be the species responsible for the most neurotoxic effects associated with the disease. Strategies to ameliorate the toxicity of these intermediate Aβ42 oligomeric species include the use of short, Aβ42-interacting peptides that either inhibit the formation of the Aβ42 oligomeric species or promote their conversion to high-molecular-weight aggregates. We therefore designed such an Aβ42-interacting peptide that is based on the β-hairpin amino acid sequence of the APPI, which exhibits high similarity to the β-sheet-like aggregation site of Aβ42. Upon tight binding of this 20-mer cyclic peptide to Aβ42 (in a 1:1 molar ratio), the formation of Aβ42 aggregates was enhanced, and consequently, Aβ42-mediated cell toxicity was ameliorated. We showed that in the presence of the cyclic peptide, interactions of Aβ42 with both plasma and mitochondrial membranes and with phospholipid vesicles that mimic these membranes were inhibited. Specifically, the cyclic peptide inhibited Aβ42-mediated mitochondrial membrane depolarization and reduced Aβ42-mediated apoptosis and cell death. We suggest that the cyclic peptide modulates Aβ42 aggregation by enhancing the formation of large aggregates─as opposed to low-molecular-weight intermediates─and as such has the potential for further development as an AD therapeutic.

Spatial and temporal dynamics of a Nassau grouper fish spawning aggregation located on an isolated seamount in Puerto Rico

Abstract The Nassau grouper, Epinephelus striatus, is a slow‐growing, late‐maturing, long‐lived reef fish widely distributed throughout the south‐western North Atlantic. Known for forming large spawning aggregations, numbering tens of thousands, they are now listed as Critically Endangered by the International Union for Conservation of Nature (IUCN). Recently, the only Nassau grouper spawning aggregation in Puerto Rico was documented at Bajo de Sico, a seamount and seasonally closed marine protected area. Studies elsewhere on the spatio‐temporal dynamics of Nassau grouper aggregations have documented how, and how far, fish move from home sites to the spawning site, and have shown the tight link between aggregation formation and the lunar cycle. However, these studies have not evaluated the potential impacts of the reduced spatial extent represented by a seamount, nor have they addressed the impacts of local seasonal protection relative to the size of the closed area and the timing of aggregation formation. Acoustic telemetry was used to quantify the spatio‐temporal dynamics of Nassau grouper spawning aggregation formation at Bajo de Sico. Twenty‐six individuals were tagged and tracked over three consecutive spawning seasons. Nassau grouper formed three or four aggregations per season, corresponding to the lunar cycles from January to April. Individuals displayed high visitation rates to the aggregation site: 98% visited at least two peaks per season; 80% visited multiple seasons. The timing of arrival, departure, and residency at the site were significantly different among individuals and lunar months, indicating significant variability in aggregation formation. Nassau grouper occupied a relatively small staging area (2.7 km2) and courtship arena (0.67 km2) compared with aggregations occurring on continental/insular platforms or large atolls; movements off the seamount may occur but were not detected. Results indicate the current seasonal closure inadequately protects the spawning population on Bajo de Sico and should be extended to the end of June.

Decline or shifting distribution? A first regional trend assessment for white sharks (Carcharodon carcharias) in South Africa

Unprecedented levels of change in ocean ecosystems bring an ever-increasing need for re-analyses of existing data to explore pressing conservation questions. Substantial declines in white shark (Carcharodon carcharias) presence at two primary aggregation sites have raised concerns about the species’ status throughout South Africa. Using the most comprehensive suite of abundance indices compiled to date, we evaluated temporal trends and the strength of evidence for regional redistribution. Individual indices from all primary aggregation sites in South Africa were highly variable. The overall temporal trend from a log-linear Generalized Additive Model was relatively flat, indicating largely unchanged abundance throughout South Africa since protection in 1991. However, reports of human-shark incidents showed a general shift from the Western to the Eastern Cape. Correlations among individual abundance indices demonstrated that movements were not as simple as animals leaving one site to inhabit another. Further research is needed to explore the effect of movement on monitoring data. Our results reaffirm the need for better standardization in data collection methods to generate abundance indices and to develop long-term monitoring programs on the Eastern Cape. Ideally, environmental or operational factors affecting abundance indices should also be explored in future status assessments at a regional level. Our results provide a baseline for future work, directing research to understand drivers of localized and regional changes and focusing management on reducing anthropogenic sources of mortality within their Southwest Indian Ocean range.

Absolute Abundance Estimates of Atlantic Goliath Grouper (Epinephelus itajara) on Spawning Aggregation Sites

Reliable data on Atlantic Goliath Grouper abundance are prerequisite to informed management decisions, particularly as the State of Florida reopened a limited harvest on the species in 2023 after a 32-year moratorium. Limited data exist for this purpose and fisheries data have been unavailable for over three decades due to a fishery closure that began in 1990. The purpose of this study was to compare absolute abundance estimates of Goliath Grouper between two years using an efficient, cost-effective method developed by Koenig. An underwater tagging method was used to collect mark and resight data for use in a Peterson deterministic model. These data were collected at the same spawning aggregation sites off Jupiter, Florida near the time of the new moon in September 2013 and August 2022. We found that Goliath Grouper abundance had declined at all but one of six sites since 2013. Because data were not collected during the intervening years, interannual variability is unknown. However, given the highly age-structured spawning stock of adult Goliath Grouper on the spawning grounds, the lower abundances measured in 2022 may reflect a real decline in the population rather than just representing a weak year of adult recruitment to these spawning sites.

DISPLAY OF COVID 19 INFORMATION ON HOTEL WEBPAGES- A CONTENT ANALYSIS

Purpose: The novel coronavirus (Covid-19) has pushed the hospitality industry towards an unprecedented crisis. Hotels around the world were under tremendous pressure to survive through this pandemic by adopting safety guidelines and communication with customers. This study examines the policies about safety guidelines of Indian hotels on Covid-19 with the help of their web pages, as reflected on the biggest aggregator website of India.Design: The study investigates the web pages of hotels in Agra, Delhi, and Jaipur, as shown in the biggest aggregator website of India, make my trip application and website using content analysis.Methodology: The authors consider coded statements and words, which the Government of India prescribed to the hotels for ensuring the protection against Covid-19.Implications: The study has the potential to understand the different policies adopted by the Indian hotels on Covid-19. The information obtained could help the customers to choose the right hotels for them during the pandemic. It could also provide suggestions to hotels interested in initiating best practices on dealing with Covid-19.

Investigating the influence of bentonite colloids on strontium sorption in granite under various hydrogeochemical conditions

The disposal of high-level radioactive waste in deep geological repositories is a critical environmental issue. The presence of bentonite colloids generated in the engineering barrier can significantly impact the transport of radionuclides, but their effect on radionuclide sorption in granite remains poorly understood. This study aimed to investigate the sorption characteristics of strontium (Sr) on granite as well as on the coexistence system of granite and colloids under various hydrogeochemical conditions, through batch experiments. Fourier transform infrared spectroscopy was employed to analyze the sorption forms of Sr on granite before and after sorption. Several hydrogeochemical factors were examined, including contact time, pH, ionic strength, coexisting ions, and bentonite and humic acid colloid concentration. Among these factors, the concentration of bentonite colloids exhibited a significant effect on Sr sorption. Within a specific range of colloid concentration, the sorption of Sr on the solid system increased linearly with the bentonite colloid concentration. pH and ionic strength were also found to play crucial roles in the sorption process. At low pH, Sr sorption primarily occurred through the outer sphere's surface complexation and Na+/H+ ion exchange. However, at high pH, inner sphere surface complexation dominated the process. As the ionic strength increased, electrostatic repulsion gradually increased, resulting in fewer binding sites for particle aggregation and Sr sorption on bentonite colloids. The results also indicate that with increasing pH, the predominant forms of Sr in the solution transitioned from SrHCO3+ and SrCl+ to SrCO3 and SrCl+. This was mainly due to the ion exchange of Ca2+/Mg2+ in plagioclase and biotite, forming SrCO3 precipitation. These findings provide valuable insights into the transport behavior of radionuclides in the subsurface environment of the repository and highlight the importance of considering bentonite colloids and other hydrogeochemical factors when assessing the environmental impact of high-level radioactive waste disposal.

Study on the Remediation of Pyrene-Contaminated Soil with Surfactants and their Mechanisms

Soil is the main aggregation site of polycyclic aromatic hydrocarbons and an important pathway of migration to other media. In this paper, the adsorption behavior of pyrene and seven different types of surfactants on kaolinite surfaces was studied by molecular dynamics simulation and desorption testing. The molecular dynamics simulation results showed that pyrene was more easily adsorbed on the 001 (-) side of kaolinite. SDBS, SDS, TW80, and TX-100 had strong interactions with pyrene, encapsulating pyrene molecules in aggregates. However, when the concentration of surfactant was too high, the desorption of pyrene molecules on a kaolinite surface will be inhibited. The desorption of pyrene molecules will be inhibited in the presence of BS-12, TW80, and TX-100, while the desorption process can be promoted by using CTAC, DDBAC, SDBS, and SDS as soil remediation agents. The removal rate of pyrene gradually increased with the increase of SDS dosage, while for SDBS, the removal rate showed a trend of first increasing and then decreasing. When the concentration of SDS was 0.014 mol/L, the elution rate of pyrene reached 72.86%. The molecular dynamics simulation results were similar to the desorption test results, verifying the reliability of molecular dynamics simulation. The research results provide theoretical support for the selection of surfactants in the remediation process of pyrene-contaminated soil.

Understanding multi-sited early village communities of the American Southeast through categorical identities and relational connections

Early villages are often assumed to be economically and politically autonomous and equivalent to an archaeological socio-spatial unit that represents a maximum scale of cohesive residential communities. But the boundaries of some communities extended far beyond such sites of early population aggregation. In the coastal plain of the American Southeast, early village communities of the Middle and Late Woodland period (ca. 100 to 1000 CE) were located at civic-ceremonial centers that hosted periodic large-scale events, including feasting and mound building. These places regularly integrated mobile populations and permanent residents, arguably creating translocal communities that were both spatially expansive and densely integrated. We employ social network analysis as a way of identifying the spatial extent, composition, and structure of these translocal communities. We compare relational connections via a database of shared makers’ marks on Swift Creek Complicated Stamped pottery with categorical identities revealed in temporally constrained pottery type frequencies. We find that most early villages in this region were far from autonomous and instead were characterized by frequent relational connections and shared categorical identities spanning hundreds of kilometers, with civic-ceremonial centers serving as central nodes of interaction within and between spatially dispersed communities.

Rural human capital in the conceptual optics: Continuum and/or post-ism?

In explanatory dictionaries, “post” is interpreted either as a prefix that has the same meaning as the word “after” (the most obvious and well-known examples from the social sphere are post-imperialist or post-colonial (world), post-Soviet (period), post-socialist (countries), etc.), or as the first part of compound words, denoting what exists/happens based on the second part of the word (post-impressionism, postmodernism, post-industrial, etc.) [see, e.g.: 4]. On aggregator websites of definitions from different dictionaries [see, e.g.: 13], “post” is interpreted mainly as a prefix denoting something that occurs after something, but in relation to philosophical trends of the end of the 20th century (postmodernism, postpositivism, poststructuralism, etc.), it is not only about “after”, but also about a kind of (not dialectical or negative) denial of immediate predecessors - as changing (or destroying) the accepted ideas about the hierarchy of attitudes and methods, which can be applied to human activities beyond philosophy (post-capitalism, postcommunism, post-Fordism, etc.) [see, e.g.: 15]. The lexical and research legitimacy of the prefix “post” has not been questioned for a long time, it is taken for granted in scientific and official discourses; however, the question is whether this “tool” of analytical conceptualization is universal or it has a distorting effect on research “optics” and “rhetoric” and, accordingly, a discriminatory effect on the corresponding objective realities, given the heterogeneity of most contemporary social-economic and other processes. In particular, whether we can use concepts with the prefix “post” to assess the state and prospects of the so-called “human capital”, considering its variability on the conditional but already traditional “rural-urban continuum”. The article presents an attempt to provide a preliminary assessment of the universality (or limitations) of the concepts with the prefix “post” in the study of the rural “cluster” of human capital.

Assessing the Movements, Habitat Use, and Site Fidelity of the Giant Freshwater Whipray (Urogymnus polylepis) with Acoustic Telemetry in the Maeklong River, Thailand

We used acoustic telemetry to assess site fidelity, movement patterns, and habitat use within the lower Maeklong River, Thailand, by 22 giant freshwater whipray Urogymnus polylepis. This study is the first of its kind for this rare, endangered species, and it begins to fill critical information gaps about its ecology and life history. Study animals were tagged subcutaneously in the dorsal area with acoustic transmitters and tracked for 12 months using a fixed array of eight receivers. Receivers were positioned within an 18 rkm section of the Maeklong, starting approximately 4 rkm upstream from the mouth. We calculated individual residency indices, tracked longitudinal movements, and assessed annual and seasonal patterns of site use. We also investigated spatial use patterns, diel activity patterns, and relationships of temperature and site fidelity. We detected 86% of our tagged whiprays, 53% of which were detected for the majority of the study period. Whiprays exhibited high site fidelity across seasons. Individuals made long longitudinal movements within the site for much of the study period but seemed to remain closer to the estuary during the second half of the rainy season and early winter. All receivers had large numbers of detections, but upstream receivers were visited for longer time durations than downstream receivers. A receiver in the middle of the study area had the highest detection rate, but low detection durations, suggesting that this receiver is in a migration corridor. A mix of immature and mature males and females was present in the site throughout the study period, suggesting that this area is not exclusively a breeding or nursery site. However, the high site fidelity suggests that this is an important aggregation site for the species. Effective conservation measures may include conservation zones and a shrimp reintroduction program upstream, ensuring fish passage through the middle of the site, and regulating traffic and pollution downstream. We found acoustic telemetry to be an effective study method and encourage its use to improve understanding of the giant freshwater whipray.

Tracing Jewish family history in a post-Holocaust world

ABSTRACT The growth in online platforms and documentary aggregator sites has revolutionised the process of Jewish family history research. This article records how the loss of EU citizenship rights following Britain’s departure from the European Union encouraged the author to investigate their own family history. Drawing upon the author’s findings, it describes how communal record books left on the shelves of town halls across Romania for over a century have been given new life thanks to the efforts of community archivists. This article chronicles their efforts to identify, preserve and digitise these documents which help to shed light on the history of the Jewish community of Dorna Watra, now Vatra Dornei, a small town in the former Austrian crownland of Bukovina. This article provides a detailed evaluation of the opportunities facing Jewish family researchers and the strengths and weaknesses of online aggregator sites such as Ancestry.Com and JewishGen.

Patterns of overlapping habitat use of juvenile white shark and human recreational water users along southern California beaches.

Juvenile white sharks (JWS) of the Northeastern Pacific population are present in nearshore southern California waters and form mixed size class (~1.5-3 m) aggregations for weeks to months, often within 500 m of shore. These nearshore beach habitats are heavily used for human recreation (e.g., surfing, swimming, body boarding, wading, and standup paddleboarding) and the amount of spatio-temporal overlap between JWS and humans is currently unknown. Increases in human population and the Northeastern Pacific population of white sharks have raised concern over human beach safety. To determine spatio-temporal JWS-human overlap at various spatial scales (e.g., across the entire southern California coastline, across different distances from shore, and within specific beach locations), 26 beach locations across southern California were surveyed monthly resulting in 1644 aerial drone surveys between January 2019 to March 2021. Thirteen environmental variables were assessed to predict when spatio-temporal overlap between JWS and water users was highest. Coast-wide distribution of JWS was clumped, limiting human-shark co-occurrence to specific locations, with 1096 of 1204 JWS observations occurring at Carpinteria and Del Mar Beach locations. Nearshore distribution indicated JWS are often close enough to the wave break to interact with some water users (median = 101 m, range = 2-702 m), although JWS had the most spatial overlap with stand-up paddlers. Daily human-shark co-occurrence was 97% at beaches where JWS aggregations had formed, and human activity showed high spatial overlap at shark aggregation sites. Although there is higher seasonal human-shark spatio-temporal overlap where aggregations form in southern California, the number of unprovoked shark bites across southern California is extremely low. This study provides evidence that high human-shark spatio-temporal overlap does not lead to an increased bite frequency in southern California, and there are a number of possible explanations as to why JWS are not biting water users despite daily encounters.

The geometric microliths of cueva de la cocina and their significance in the mesolithic of Eastern Iberia: A morphometric study

This work presents the analysis of the geometric microliths of Cueva de la Cocina (València, Spain). It does so considering the hypothesis that, given the size of the cave's assemblage and its distinctive cultural markers, it could have acted as an aggregation site for the Late Mesolithic in the Mediterranean Iberia. The work presented here uses the cultural similarity of the geometric microliths of different sites to test this hypothesis, relying on several methodological techniques such as tactical simulation and geometric morphometrics, while offering proposals for the correction of data imbalance in archaeological data. As a conclusion, our data points to the fact that, for the last phase of the Late Mesolithic (phase B in the regional sequence) the site could have indeed acted as an aggregation site, but we require caution on the results of our analysis fundamentally on two grounds: (1) whether the cultural variation of the geometric microliths offers enough resolution for microscale analysis and (2) the necessity to combine this proxy with other types of archaeological artefacts which could give (or rest) strength to our hypothesis.

An ER-accumulated mutant of yeast Pma1 causes membrane-related stress to induce the unfolded protein response

Upon dysfunction of the endoplasmic reticulum (ER), namely ER stress, eukaryotic cells provoke the unfolded protein response (UPR), which is triggered by ER stress sensors including Ire1. While the ER luminal domain of Ire1 is known to directly recognize misfolded soluble proteins accumulated in the ER, the transmembrane domain of Ire1 is involved in its self-association and activation upon membrane lipid-related abnormalities, which are so-called lipid bilayer stress (LBS). Here we inquired how the ER accumulation of misfolded transmembrane proteins induces the UPR. In yeast Saccharomyces cerevisiae cells, a multi-transmembrane protein, Pma1, is not transported to the cell surface but aggregates on the ER membrane when carrying a point mutation (Pma1-2308). Here, we show that GFP-tagged Ire1 co-localized with the Pma1-2308-mCherry puncta. This co-localization and the UPR induced by Pma1-2308-mCherry were compromised by a point mutation in Ire1 that specifically impairs its activation upon LBS. We presume that Pma1-2308-mCherry locally affects the properties (probably the thickness) of the ER membrane at its aggregation sites, where Ire1 is then recruited, self-associated, and then activated.

Parasitic Copepods as Biochemical Tracers of Foraging Patterns and Dietary Shifts in Whale Sharks (Rhincodon typus Smith, 1828)

Understanding the diet of whale sharks (Rhincodon typus) is essential for the development of appropriate conservation strategies for the species. This study evaluated the use of the parasitic copepod (Pandarus rhincodonicus) as a proxy to infer short-term foraging habitats and trophic positions of whale shark hosts. To accomplish this, bulk stable carbon (δ13C) and nitrogen (δ15N) isotope compositions were analysed from 72 paired samples of whale shark skin (dermal) tissues and copepods collected across six years at the Ningaloo Reef aggregation site, Western Australia. This study found that δ15N from parasites and whale shark hosts were strongly correlated. As turn-over times of the parasite and whale shark differ (months vs. years, respectively), the ability of copepods to predict δ15N values indicates that the trophic positions of whale sharks remain consistent across these timeframes. Contrastingly, δ13C in the parasite and host were weakly correlated, likely reflecting differences in the physiology and lifecycle of the copepod parasite compared to the host. Our results suggest δ15N from parasitic copepods provides a reliable proxy of the trophic position of their whale shark hosts, but interpretation of δ13C values as a proxy for the host will require future studies on the lifecycle of P. rhincodonicus.

Marine reserve use by a migratory coastal shark, Carcharias taurus

Networks of small no-take marine protected areas (MPAs) are a popular approach to protect mobile marine species at key sites along their migration routes. Understanding how individuals vary in their use of these sites is needed to ensure MPA networks are optimised to offer maximum protection benefits. Using diver-led surveys, coded acoustic tags and a continental-scale collaborative network of acoustic receivers, we investigated variation in the use of three Australian MPAs by aggregating grey nurse sharks, Carcharias taurus. The Wolf Rock MPA was used year-round by C. taurus and as a gestation site, with females spending up to 254 d at the site with 2.2–3.7 year absences between residencies. In contrast, Flat Rock and Cherubs Cave-Henderson Rock MPAs were used as a transitory aggregation site with males and females occurring at the site for 30 min–59 d intervals between June–January, only. Migratory movements ranged up to 1500 km along the coastline, intersected 18 MPAs and/or recognised C. taurus aggregation sites, and connected temperate waters at Montague Island (36.25° S) with that of the southern Great Barrier Reef (23.40° S). Our study demonstrates how local receiver arrays and national collaborative acoustic telemetry networks are powerful tools to reveal use, fidelity and connectivity of MPA networks by marine migratory species. As the east Australian C. taurus population is critically endangered and at particular risk of anthropogenic threats, ongoing monitoring of the species' movement behaviour and complementary management outside protected area boundaries is warranted to assist its protection.

Influencing Perception of Frailty Risk in Urban and Rural Older Adults

Aims To investigate the effect of frailty education on the perception of frailty risk for urban and rural older adults. Methods Forty adults completed a frailty perception survey, the Edmonton Frail Scale (EFS), and participated in a 6-week frailty intervention program. Results Urban older adults increased knowledge of frailty including identification of frailty risk (.0035, p < .05), importance of good nutrition as we age (.0015, p < .05) and confidence in accessing community resources (.000031, p < .05). Aggregate site results showed increased accessibility to frailty education including risk of frailty (2.24576E-12, p < .05), frailty criteria (3.29825E-12, p < .05), and reduction of frailty risk (1.21856E-09, p < .05) for rural and urban older adults. Fall prevention knowledge improved at both Urban and Rural A sites (.00021, p < .05). Conclusions The frailty education provided to urban and rural community dwelling older adults supported a change in the perceptions of frailty risk after participation in the program.