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1.
J Fish Biol ; 104(4): 1122-1135, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38193568

RESUMEN

Population estimates are required for effective conservation of many rare marine species, but can be difficult to obtain. The critically endangered red handfish (Thymichthys politus) is a coastal anglerfish known only from two fragmented populations in southeast Tasmania, Australia. It is at a high risk of extinction due to low numbers, loss of habitat, and the impacts of climate change. To aid conservation efforts, we provide the first empirical population size estimates of red handfish and investigate other important aspects of the species' life history, such as growth, habitat association, and movement. We surveyed both red handfish local populations via underwater visual census on scuba over 3 years and used photographic mark-recapture techniques to estimate biological parameters. In 2020, the local adult population size was estimated to be 94 (95% confidence interval [CI] 40-231) adults at one site, and 7 (95% CI 5-10) at the other site, suggesting an estimated global population of 101 adults. Movement of individuals was extremely limited at 48.5 m (± 77.7 S.D.) per year. We also found evidence of declining fish density, a declining proportion of juveniles, and increasing average fish size during the study. These results provide a serious warning that red handfish are likely sliding toward extinction, and highlight the urgent need to expand efforts for ex situ captive breeding to bolster numbers in the wild and maintain captive insurance populations, and to protect vital habitat to safeguard the species' ongoing survival in the wild.


Asunto(s)
Conservación de los Recursos Naturales , Especies en Peligro de Extinción , Animales , Conservación de los Recursos Naturales/métodos , Extinción Biológica , Peces , Ecosistema
2.
Pediatr Emerg Care ; 40(4): 311-313, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37665787

RESUMEN

OBJECTIVES: After the establishment of the virtual pediatric emergency medicine clinic at our institution, we noted that several physicians independently began to instruct caregivers virtually on reducing a radial head subluxation. We thus conducted a case series to investigate the number, success, and follow-ups for the virtual reduction of radial head subluxation. METHODS: The electronic medical records at our institution were searched from the inception of the virtual clinic in May 2020 until August 2022 (inclusive), for visits and discharge diagnosis containing the word "elbow" or "arm." RESULTS: Fourteen charts were retrieved; however, 2 were excluded because they were not a suspected radial head subluxation. A virtual reduction was attempted for eight (66.7%) of the 12 patients. In 6 of 8 patients (75.0%), the reduction was deemed successful, and for 2 patients (25.0%), it was deemed unsuccessful. Of the latter, one was found to have a nondisplaced radial neck fracture. All 4 patients (33.3%) for whom a virtual reduction was not attempted were referred to the emergency department. CONCLUSIONS: Virtual video coaching of pulled elbow reduction was completed at our institution with overall good success rate. All the physicians involved noted the essential need and benefits of video conferencing for successfully reducing radial head subluxation. We note that a pediatric population may be more amenable to video-based appointments than other populations due to their caregivers' familiarity with digital technology. Finally, as nonphysician models of healthcare delivery for virtual urgent care visits expand, we propose a checklist based on our experience to ensure patient safety.


Asunto(s)
Lesiones de Codo , Articulación del Codo , Luxaciones Articulares , Tutoría , Fracturas del Radio , Humanos , Niño , Luxaciones Articulares/terapia , Fracturas del Radio/complicaciones
3.
Sci Rep ; 11(1): 15267, 2021 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-34413322

RESUMEN

Scuba-divers on tropical coral-reefs often report unprovoked "attacks" by highly venomous Olive sea snakes (Aipysurus laevis). Snakes swim directly towards divers, sometimes wrapping coils around the diver's limbs and biting. Based on a focal animal observation study of free-ranging Olive sea snakes in the southern Great Barrier Reef, we suggest that these "attacks" are misdirected courtship responses. Approaches to divers were most common during the breeding season (winter) and were by males rather than by female snakes. Males also made repeated approaches, spent more time with the diver, and exhibited behaviours (such as coiling around a limb) also seen during courtship. Agitated rapid approaches by males, easily interpreted as "attacks", often occurred after a courting male lost contact with a female he was pursuing, after interactions between rival males, or when a diver tried to flee from a male. These patterns suggest that "attacks" by sea snakes on humans result from mistaken identity during sexual interactions. Rapid approaches by females occurred when they were being chased by males. Divers that flee from snakes may inadvertently mimic the responses of female snakes to courtship, encouraging males to give chase. To prevent escalation of encounters, divers should keep still and avoid retaliation.

4.
Ecol Evol ; 8(18): 9372-9383, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30377508

RESUMEN

Collecting data on unlicensed open-access coastal activities, such as some types of recreational fishing, has often relied on telephone interviews selected from landline directories. However, this approach is becoming obsolete due to changes in communication technology such as a switch to unlisted mobile phones. Other methods, such as boat ramp interviews, are often impractical due to high labor cost. We trialed an autonomous, ultra-high-resolution photosampling method as a cost effect solution for direct measurements of a recreational fishery. Our sequential photosampling was batched processed using a novel software application to produce "big data" time series movies from a spatial subset of the fishery, and we validated this with a regional bus-route survey and interviews with participants at access points. We also compared labor costs between these two methods. Most trailer boat users were recreational fishers targeting tuna spp. Our camera system closely matched trends in temporal variation from the larger scale regional survey, but as the camera data were at much higher frequency, we could additionally describe strong, daily variability in effort. Peaks were normally associated with weekends, but consecutive weekend tuna fishing competitions led to an anomaly of high effort across the normal weekday lulls. By reducing field time and batch processing imagery, Monthly labor costs for the camera sampling were a quarter of the bus-route survey; and individual camera samples cost 2.5% of bus route samples to obtain. Gigapixel panoramic camera observations of fishing were representative of the temporal variability of regional fishing effort and could be used to develop a cost-efficient index. High-frequency sampling had the added benefit of being more likely to detect abnormal patterns of use. Combinations of remote sensing and on-site interviews may provide a solution to describing highly variable effort in recreational fisheries while also validating activity and catch.

5.
PLoS One ; 13(8): e0201518, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30102710

RESUMEN

The critically endangered spotted handfish (Brachionichthys hirsutus) is restricted to a limited number of locations in south-eastern Tasmania, Australia. As is often the case for rare species, conducting statistically adequate surveys for B. hirsutus can be costly and time consuming due to the low probability of encountering individuals. For the first time we used a highly efficient and rigorous Global Positioning System (GPS) parameterised underwater visual census (GUVC) to survey B. hirsutus abundance within all nine known local populations in the Derwent Estuary within one season. In addition, a benthic microhabitat assessment was conducted simultaneously using a GoPro® camera attached to diver to determine B. hirsutus microhabitat preferences. B. hirsutus local populations varied between sites, with densities ranging from 1.58 to 43.0 fishes per hectare. B. hirsutus demonstrates a strong preference for complex microhabitat features, such as depressions and ripple formations filled with biogenic substrates (e.g. shells) but avoids simple, low relief microhabitats (e.g. sand flats) and areas dominated by ephemeral, filamentous algae. Complex microhabitats may enable B. hirsutus to avoid predators, increase forage opportunities or provide higher quality spawning sites. This first wide-scale application of GUVC for B. hirsutus allowed us to survey a larger number of sites than previously possible to provide a robust reference point for future long-term monitoring.


Asunto(s)
Distribución Animal/fisiología , Ecosistema , Especies en Peligro de Extinción , Peces/fisiología , Sistemas de Información Geográfica , Animales , Conducta Alimentaria/fisiología , Tecnología de Sensores Remotos/instrumentación , Tecnología de Sensores Remotos/métodos , Reproducción/fisiología , Tasmania , Grabación en Video/instrumentación , Grabación en Video/métodos
6.
Pediatr Emerg Care ; 34(9): 650-655, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28328691

RESUMEN

OBJECTIVES: The transfer of children from community emergency departments (EDs) to tertiary care pediatric EDs for investigations, interventions, or a second opinion is common. In order to improve health care system efficiency, we must have a better understanding of this population and identify areas for education and capacity building. METHODS: We conducted a retrospective chart review of all patients (aged 0-17 years) who were transferred from community ED to a pediatric ED from November 2013 to November 2014. The primary outcome was the frequency of referred patients who were discharged home from the pediatric ED. RESULTS: Two hundred four patients were transferred from community EDs in the study period. One hundred thirteen children (55.4%) were discharged home from the pediatric ED. Presence of inpatient pediatric services (P = 0.04) at the referral hospital and a respiratory diagnosis (P = 0.03) were independently associated with admission to the children's hospital. In addition, 74 patients (36.5%) had no critically abnormal vital signs at the referral hospital and did not require any special tests, interventions, consultations, or admission to the children's hospital. Younger age (P = 0.03), lack of inpatient pediatric services (P = 0.04), and a diagnosis change (P = 0.03) were independently associated with this outcome. CONCLUSIONS: More than half of patients transferred to the pediatric tertiary care ED did not require admission, and more than one third did not require special tests, interventions, consults, or admission. Many of these patients were likely transferred for a second opinion from a pediatric emergency medicine specialist. Education and real-time videoconferencing consultations using telemedicine may help to reduce the frequency of transfers for a second opinion and contribute to cost savings over the long term.


Asunto(s)
Servicio de Urgencia en Hospital/estadística & datos numéricos , Hospitales Comunitarios/estadística & datos numéricos , Hospitales Pediátricos/estadística & datos numéricos , Alta del Paciente/estadística & datos numéricos , Transferencia de Pacientes/estadística & datos numéricos , Adolescente , Niño , Preescolar , Estudios de Cohortes , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Lactante , Masculino , Estudios Retrospectivos
7.
Ecol Evol ; 6(19): 6963-6968, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-28725373

RESUMEN

Successful marine management relies on understanding patterns of human use. However, obtaining data can be difficult and expensive given the widespread and variable nature of activities conducted. Remote camera systems are increasingly used to overcome cost limitations of conventional labour-intensive methods. Still, most systems face trade-offs between the spatial extent and resolution over which data are obtained, limiting their application. We trialed a novel methodology, CSIRO Ruggedized Autonomous Gigapixel System (CRAGS), for time series of high-resolution photo-mosaic (HRPM) imagery to estimate fine-scale metrics of human activity at an artificial reef located 1.3 km from shore. We compared estimates obtained using the novel system to those produced with a web camera that concurrently monitored the site. We evaluated the effect of day type (weekday/weekend) and time of day on each of the systems and compared to estimates obtained from binocular observations. In general, both systems delivered similar estimates for the number of boats observed and to those obtained by binocular counts; these results were also unaffected by the type of day (weekend vs. weekday). CRAGS was able to determine additional information about the user type and party size that was not possible with the lower resolution webcam system. However, there was an effect of time of day as CRAGS suffered from poor image quality in early morning conditions as a result of fixed camera settings. Our field study provides proof of concept of use of this new cost-effective monitoring tool for the remote collection of high-resolution large-extent data on patterns of human use at high temporal frequency.

8.
PLoS One ; 9(12): e113652, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25517905

RESUMEN

Sustained observations allow for the tracking of change in oceanography and ecosystems, however, these are rare, particularly for the Southern Hemisphere. To address this in part, the Australian Integrated Marine Observing System (IMOS) implemented a network of nine National Reference Stations (NRS). The network builds on one long-term location, where monthly water sampling has been sustained since the 1940s and two others that commenced in the 1950s. In-situ continuously moored sensors and an enhanced monthly water sampling regime now collect more than 50 data streams. Building on sampling for temperature, salinity and nutrients, the network now observes dissolved oxygen, carbon, turbidity, currents, chlorophyll a and both phytoplankton and zooplankton. Additional parameters for studies of ocean acidification and bio-optics are collected at a sub-set of sites and all data is made freely and publically available. Our preliminary results demonstrate increased utility to observe extreme events, such as marine heat waves and coastal flooding; rare events, such as plankton blooms; and have, for the first time, allowed for consistent continental scale sampling and analysis of coastal zooplankton and phytoplankton communities. Independent water sampling allows for cross validation of the deployed sensors for quality control of data that now continuously tracks daily, seasonal and annual variation. The NRS will provide multi-decadal time series, against which more spatially replicated short-term studies can be referenced, models and remote sensing products validated, and improvements made to our understanding of how large-scale, long-term change and variability in the global ocean are affecting Australia's coastal seas and ecosystems. The NRS network provides an example of how a continental scaled observing systems can be developed to collect observations that integrate across physics, chemistry and biology.


Asunto(s)
Fenómenos Biológicos , Fenómenos Químicos , Oceanografía/métodos , Fenómenos Físicos , Australia , Laboratorios , Oceanografía/instrumentación , Fitoplancton , Control de Calidad , Estadística como Asunto , Telemetría , Temperatura
9.
Environ Manage ; 52(6): 1341-54, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24213854

RESUMEN

Between 2001 and 2009, 26 marine-protected areas (MPA) were established on the east Australian seaboard, at least in part, to manage human interactions with a critically endangered population of grey nurse shark, Carcharias taurus. This network is spread across six MPA systems and includes all 19 sites outlined in the National Recovery Plan for C. taurus, though five sites remain open to some forms of fishing. The reserve network has complex cross-jurisdictional management, as the sharks occur in waters controlled by the Australian states of New South Wales (NSW) and Queensland, as well as by the Commonwealth (Federal) government. Jurisdiction is further complicated by fisheries and conservation departments both engaging in management activities within each state. This has resulted in protected area types that include IUCN category II equivalent zones in NSW, Queensland, and Commonwealth marine parks that either overlay or complement another large scaled network of protected sites called critical habitats. Across the network, seven and eight rule permutations for diving and fishing, respectively, are applied to this population of sharks. Besides sites identified by the recovery plan, additional sites have been protected as part of the general development of MPA networks. A case study at one of these sites, which historically was known to be occupied by C. taurus but had been abandoned, appears to shows re-establishment of an aggregation of juvenile and sub-adult sharks. Concurrent with the re-establishment of the aggregation, a local dive operator increased seasonal dive visitation rates at the site fourfold. As a precautionary measure, protection of abandoned sites, which includes nursery and gestating female habitats are options that may assist recovery of the east coast population of C. taurus.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Especies en Peligro de Extinción , Explotaciones Pesqueras/métodos , Programas de Gobierno/organización & administración , Tiburones/fisiología , Animales , Conservación de los Recursos Naturales/legislación & jurisprudencia , Conservación de los Recursos Naturales/estadística & datos numéricos , Buceo/economía , Buceo/estadística & datos numéricos , Explotaciones Pesqueras/legislación & jurisprudencia , Programas de Gobierno/legislación & jurisprudencia , Humanos , Nueva Gales del Sur , Océano Pacífico , Queensland , Recreación/economía
10.
Conserv Biol ; 20(5): 1466-76, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17002764

RESUMEN

Theoretical models of marine protected areas (MPAs) that explore benefits to fisheries or biodiversity conservation often assume a dynamic pool of fishing effort. For instance, effort is homogenously distributed over areas from which subsets of reserves are chosen. I tested this and other model assumptions with a case study of the multiple-use Jervis Bay Marine Park. Prior to zoning of the park I conducted 166 surveys of the park's recreational fisheries, plotting the location of 16,009 anglers. I converted these plots into diagrams of fishing effort and analyzed correlates between fishing and habitat and the effect of two reserve designs-the draft and final zoning plans of the park-on the 15 fisheries observed. Fisheries were strongly correlated with particular habitats and had negatively skewed and often bimodal spatial distribution. The second mode of intensely fished habitat could be 6 SD greater than the fishery's mean allocation of effort by area. In the draft-zoning plan, sanctuary zone (no-take) area and potential subduction of fishing effort were similar. In the final plan, which was altered in response to public comment, the area of sanctuary zone increased, and the impact on fishing effort decreased. In only one case was a fishery's most intensely targeted location closed to fishing. Because of the discriminating manner with which fishers target habitats, if simple percentage targets are used for planning, sanctuary location can be adjusted to avoid existing fishing effort. According to modeled outcomes, the implication of this may be diminished reserve effectiveness. To address this, reserve area should be implicitly linked to subducted fishing effort when promoting or modeling MPAs.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Explotaciones Pesqueras , Recreación , Modelos Biológicos , Nueva Gales del Sur , Océanos y Mares
11.
Environ Manage ; 33(2): 196-211, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15285398

RESUMEN

The New South Wales State Government (Australia) gazetted the Jervis Bay Marine Park (JBMP) in 1998. During the preparation of the draft zoning plan in 2000, societal data on two conflicting park user groups--recreational scuba divers and fishers (anglers)--was collected. While conflict resolution was a plan priority, other factors, such as cumulative environmental impacts of users and protection for the critically endangered grey nurse shark (Carcharias taurus), further complicated planning. Both scuba diving and angling are primary summer activities and are disproportionately concentrated around the headlands of the bay. Furthermore, shore based game-fishing was concentrated on the northern headland, where the conflict was centered. However, when the exact locations of divers and anglers were determined, there was a partial partitioning of the available space, with only a small contested overlap. To resolve conflict and maximize positive environmental outcomes, a sanctuary zone and noanchoring zone option in the draft zoning plan was sought to formalize this partition. The human dimension data proved valuable in guiding environmental management in this politically volatile situation. A baseline study conducted 11 years previously was also used to gain a limited perspective on change in user numbers. Comparison between study periods indicated dive numbers had remained similar, while the number of dive charter trips was significantly less. The numbers of anglers, for the four months compared, had doubled and tripled. The actual data used to inform management is presented and the limitations of this "best available data" approach are discussed.


Asunto(s)
Conservación de los Recursos Naturales , Buceo , Ambiente , Explotaciones Pesqueras , Recreación , Animales , Conflicto Psicológico , Recolección de Datos , Monitoreo del Ambiente , Peces , Humanos , Nueva Gales del Sur , Solución de Problemas
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