Summer circumpolar acoustic occurrence and call rates of Ross, Ommatophoca rossii, and leopard, Hydrurga leptonyx, seals in the Southern Ocean

DATA AVAILABILITY STATEMENT : The full dataset from the Scientific Committee on Antarctic Research cruise is available on the Dryad data repository (https://doi.org/10.5061/dryad.rr4xgxd79). Acoustic data from International Whaling Commission’s Southern Ocean Whale and Ecosystem Research cruises are available upon request from the International Whaling Commission’s offices.Two of the Antarctic pack ice seals, Ross, Ommatophoca rossii, and leopard, Hydrurga leptonyx, seals, are extremely difficult to study via traditional visual survey techniques, yet are ideal for an acoustic survey as they are highly vociferous and produce an array of underwater sounds during the austral summer. To determine their acoustic occurrence in the Antarctic pack ice, we use their calls, detected within 680 acoustic recordings made between 1999 and 2009 as part of two multinational programmes. Siren calls of Ross seals were detected mainly in January, and 9.88 calls per minute from low siren calls was the highest call rate for this species. High numbers of Ross seal calls were detected close to the ice edge in areas between 0° and 20° E and 60° and 130° E, suggesting these are important summer habitats. Leopard seal calls were detected mainly in December and January, and December had the highest percentage of calls. Call rate of 11.93 calls per minute from low double trills was the highest call rate for leopard seals. Leopard seal calls were detected throughout the Southern Ocean with more calls detected throughout the pack ice. There was little spatio-temporal overlap in call occurrence of Ross and leopard seals, but both species were more vocally active during the day. Longitude and latitude were the most important predictors of Ross seal occurrence, and month of the year highly predicted leopard seal occurrence. This is the first study to examine the circumpolar acoustic occurrence of Ross and leopard seals in the Southern Ocean pack ice.International Whaling Commission’s Southern Ocean Whale and Ecosystem Research cruises were conducted by the International Whaling Commission, and the Scientific Committee on Antarctic Research cruise was funded by the Antarctic Scientific Advisory Committee (ASAC 552 and 1140), the Sea World Research and Rescue Foundation Inc. and the Scott Foundation.http://link.springer.com/journal/300am2022Mammal Research Institut

Trash removal methods for improved mechanical emptying of pit latrines using a screw auger

Trash in pit latrines is one of the largest challenges facing pit emptying technologies, including the powered auger (the Excrevator), developed for improved emptying in lower- and lower-middle income countries. This study focused on two trash removal methods in conjunction with pit emptying by the Excrevator: (1) simultaneous removal of trash with sludge and (2) manual trash removal prior to sludge removal. Simultaneous removal was tested by adding to the inlet of the Excrevator system two cutting heads designed to reduce the size of trash particles before entering the pipe and auger. Laboratory testing indicated that the auger will not provide the rotational speeds necessary for proper maceration of fibrous materials such as clothing, indicating that a separate maceration unit with higher rotational methods may be more appropriate. Four manual trash removal mechanisms were designed to improve on existing manual trash ‘fishing’ tools such as iron rods with fixed hooks. Two of these tools (the ‘claw’ and the ‘hook’) showed promising laboratory results and were subsequently field tested in Mzuzu, Malawi. Both tools proved more efficient than the current tools used in the field and have potential for use in Malawi

Evolutionary predictors of mammalian home range size: body mass, diet and the environment

ABSTRACT Aim Mammalian home range patterns provide information on spatial behaviour and ecological patterns, such as resource use, that is often used by conservation managers in a variety of contexts. However, there has been little research on home range patterns outside of the terrestrial environment, potentially limiting the relevance of current home range models for marine mammals, a group of particular conservation concern. To address this gap, we investigated how variation in mammalian home range size among marine and terrestrial species was related to diet, environment and body mass. Location Global. Methods We compiled data on home range size, environment (marine and terrestrial), diet and body mass from the literature and empirical studies to obtain a dataset covering 462 mammalian species. We then used phylogenetic regression analyses (to address non-independence between species) to examine the relative contribution of these factors to variation of home range size among species. Results Body size explained the majority of the difference in home range size among species (53-85%), with larger species occupying larger home ranges. The type of food exploited by species was also an important predictor of home range size (an additional 15% of variation), as was the environment, but to a much lesser degree (1.7%). Main conclusions The factors contributing to the evolution of home ranges are more complex than has been assumed. We demonstrate that diet and body size both influence home range patterns but differ in their relative contribution, and show that colonization of the marine environment has resulted in the expansion of home range size. Broad-scale models are often used to inform conservation strategies. We propose that future integrative models should incorporate the possibility of phylogenetic effects and a range of ecological variables, and that they should include species representative of the diversity within a group

Density Can Be Misleading for Low-Density Species: Benefits of Passive Acoustic Monitoring

Climate-induced changes may be more substantial within the marine environment, where following ecological change is logistically difficult, and typically expensive. As marine animals tend to produce stereotyped, long-range signals, they are ideal for repeatable surveying. In this study we illustrate the potential for calling rates to be used as a tool for determining habitat quality by using an Antarctic pack-ice seal, the leopard seal, as a model. With an understanding of the vocal behavior of a species, their seasonal and diurnal patterns, sex and age-related differences, an underwater passive-acoustic survey conducted alongside a visual survey in an arc of 4,225 km across the Davis Sea, Eastern Antarctica, showed that while acoustic and visual surveys identified similar regions as having high densities, the acoustic surveys surprisingly identified the opposite regions as being 'critical' habitats. Density surveys of species that cannot be differentiated into population classes may be misleading because overall density can be a negative indicator of habitat quality. Under special circumstances acoustics can offer enormous advantage over traditional techniques and open up monitoring to regions that are remote, difficult and expensive to work within, no longer restricting long-term community assessment to resource-wealthy communities. As climatic change affects a broad range of organisms across geographic boundaries we propose that capitalizing on the significant advances in passive acoustic technology, alongside physical acoustics and population modeling, can help in addressing ecological questions more broadly

Stable isotopes infer the diet and habitat of the enigmatic pygmy right whale (Caperea marginata) off southern Australia

In the Southern Hemisphere, baleen whales generally undertake migrations between productive feeding grounds at high latitudes and breeding grounds at lower latitudes. Pygmy right whales (Caperea marginata) (PRW) are the smallest and most enigmatic baleen whale, that likely forgo long-distance migrations, and instead inhabit temperate and subantarctic waters year-round. Previous research has relied on limited data from sighting and stranding records to infer the habitat use and diet of PRWs, however the absence of long-term and consistent data has left uncertainty surrounding these parameters. We utilized bulk stable isotopes of carbon (δ13C) and nitrogen (δ15N) in baleen from Australian PRWs (n = 14) to infer their diet and habitat use. Stable isotope values from 1980–2019 were then matched to remote sensed data from known upwelling regions (where they likely feed) to examine if their dietary patterns are related to changes in food web dynamics. We found that PRWs remained in mid-latitude waters year-round and showed no evidence of feeding in Antarctic waters. Rather, their isotopic record suggests they remain between coastal waters off southern Australia and the Subtropical Convergence, feeding on krill and copepods. Additionally, there was a weak positive relationship between PRW nitrogen stable isotope values and sea surface temperature (SST) from the eastern Great Australian Bight (GAB) and Bonney Upwelling. This suggests seasonal changes in their diet is possibly correlated to oceanographic changes which drive food-web dynamics in these regions. Unlike larger species of baleen whales that migrate further to highly productive waters in the Southern Ocean to meet their energetic demands, the small PRW, who only reach 6.5m, may sustain both feeding and breeding requirements at mid-latitudes. This is the first study to analyze long-term dietary and movement patterns of the PRW, providing an important contribution to our understanding of the species

Estableciendo una línea de base para estudios de monitoreo: niveles leucocitarios en focas de la Península Antártica

En el contexto actual de cambio climático, resulta fundamental contar con información de base sobre parámetros inmunológicos para evaluar la magnitud y dirección del cambio sobre los organismos. El uso de parámetros hematológicos, como los conteos leucocitarios, es una herramienta útil en el análisis del estado sanitario. Los leucocitos son uno de los componentes principales del sistema inmunológico animal, brindando protección contra una gran variedad de parásitos y patógenos. En el presente estudio, presentamos por primera vez los conteos leucocitarios de tres especies de focas antárticas: Weddell (FW, Leptonychotes weddellii), Leopardo (FL, Hydrurga leptonyx) y Cangrejera (FC, Lobodon carcinophagus).Fil: D'amico, Veronica Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Leonardi, María Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; ArgentinaFil: Márquez, María Elba Isabel. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; ArgentinaFil: Rogers, Tracey L.. University of New South Wales. Faculty of Science. School of Biological-earth and Environmental Sciences; AustraliaFil: Negrete, Javier. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; Argentina. Universidad Nacional de La Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaXXX Jornadas Argentinas de MastozoologíaBahia BlancaArgentinaSociedad Argentina para el Estudio de los MamíferosInstituto de Ciencias Biológicas y Biomédicas del SurUniversidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmaci

Temporal segregation of the Australian and Antarctic blue whale call types (Balaenoptera musculus spp.)

We examined recordings from a 15-month (May 2009–July 2010) continuous acoustic data set collected from a bottom-mounted passive acoustic recorder at a sample frequency of 6kHz off Portland, Victoria, Australia (38°33′01″S, 141°15′13″E) off southern Australia. Analysis revealed that calls from both subspecies were recorded at this site, and general additive modeling revealed that the number of calls varied significantly across seasons. Antarctic blue whales were detected more frequently from July to October 2009 and June to July 2010, corresponding to the suspected breeding season, while Australian blue whales were recorded more frequently from March to June 2010, coinciding with the feeding season. In both subspecies, the number of calls varied with time of day; Antarctic blue whale calls were more prevalent in the night to early morning, while Australian blue whale calls were detected more often from midday to early evening. Using passive acoustic monitoring, we show that each subspecies adopts different seasonal and daily call patterns which may be related to the ecological strategies of these subspecies. This study demonstrates the importance of passive acoustics in enabling us to understand and monitor subtle differences in the behavior and ecology of cryptic sympatric marine mammals.This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Oxford University Press on behalf of American Society of Mammalogists. The published article can be found at: http://jmammal.oxfordjournals.org/content/96/3/603Keywords: cryptic sympatric marine mammals, seasonal, diel, Australia, calls, Balaenoptera musculus intermedia, Balaenoptera musculus brevicauda, ecology, vocalizationsKeywords: cryptic sympatric marine mammals, seasonal, diel, Australia, calls, Balaenoptera musculus intermedia, Balaenoptera musculus brevicauda, ecology, vocalization

Reliability of digital ulcer definitions as proposed by the UK Scleroderma Study Group:A challenge for clinical trial design

INTRODUCTION: The reliability of clinician grading of systemic sclerosis–related digital ulcers has been reported to be poor to moderate at best, which has important implications for clinical trial design. The aim of this study was to examine the reliability of new proposed UK Scleroderma Study Group digital ulcer definitions among UK clinicians with an interest in systemic sclerosis. METHODS: Raters graded (through a custom-built interface) 90 images (80 unique and 10 repeat) of a range of digital lesions collected from patients with systemic sclerosis. Lesions were graded on an ordinal scale of severity: ‘no ulcer’, ‘healed ulcer’ or ‘digital ulcer’. RESULTS: A total of 23 clinicians – 18 rheumatologists, 3 dermatologists, 1 hand surgeon and 1 specialist rheumatology nurse – completed the study. A total of 2070 (1840 unique + 230 repeat) image gradings were obtained. For intra-rater reliability, across all images, the overall weighted kappa coefficient was high (0.71) and was moderate (0.55) when averaged across individual raters. Overall inter-rater reliability was poor (0.15). CONCLUSION: Although our proposed digital ulcer definitions had high intra-rater reliability, the overall inter-rater reliability was poor. Our study highlights the challenges of digital ulcer assessment by clinicians with an interest in systemic sclerosis and provides a number of useful insights for future clinical trial design. Further research is warranted to improve the reliability of digital ulcer definition/rating as an outcome measure in clinical trials, including examining the role for objective measurement techniques, and the development of digital ulcer patient–reported outcome measures