Understanding how ocean currents impact the distribution and connectivity of marine species, provides vital information for the effective conservation management of migratory marine animals. Here, we used a combination of molecular genetics and ocean drift simulations to investigate the spatial ecology of juvenile green turtle (Chelonia mydas) developmental habitats, and assess the role of ocean currents in driving the dispersal of green turtle hatchlings. We analyzed mitochondrial (mt)DNA sequenced from 358 juvenile green turtles, and from eight developmental areas located throughout the Southwest Indian Ocean (SWIO). A mixed stock analysis (MSA) was applied to estimate the level of connectivity between developmental sites and published genetic data from 38 known genetic stocks. The MSA showed that the juvenile turtles at all sites originated almost exclusively from the three known SWIO stocks, with a clear shift in stock contributions between sites in the South and Central Areas. The results from the genetic analysis could largely be explained by regional current patterns, as shown by the results of passive numerical drift simulations linking breeding sites to developmental areas utilized by juvenile green turtles. Integrating genetic and oceanographic data helps researchers to better understand how marine species interact with ocean currents at different stages of their lifecycle, and provides the scientific basis for effective conservation management.
Human activities and climate change threaten marine biodiversity worldwide, though sensitivity to these stressors varies considerably by species and taxonomic group. Mapping the spatial distribution of 14 anthropogenic stressors from 2003 to 2013 onto the ranges of 1271 at-risk marine species sensitive to them, we found that, on average, species faced potential impacts across 57% of their ranges, that this footprint expanded over time, and that the impacts intensified across 37% of their ranges. Although fishing activity dominated the footprint of impacts in national waters, climate stressors drove the expansion and intensification of impacts. Mitigating impacts on at-risk biodiversity is critical to supporting resilient marine ecosystems, and identifying the co-occurrence of impacts across multiple taxonomic groups highlights opportunities to amplify the benefits of conservation management.
ZusammenfassungDie Inzidenz von Mangelernährung geriatrischer Patienten wird im Allgemeinen mit über 50 % angegeben. Mangelernährung bei geriatrischen Traumapatienten rangiert im Kollektiv der proximalen Femurfrakturen zwischen 30 und 50 %. Insgesamt erscheinen sowohl die angegebenen Häufigkeiten als auch die angewandten Messinstrumente inhomogen. Malnutrition führt zu einer Verschlechterung der Wundheilung, einer längeren postoperativen Immobilität, einem verlängerten Krankenhausaufenthalt sowie zu einer Steigerung der Mortalität. Unter Hinzuziehung bestehender Leitlinien erreichen das Mini Nutritional Assessment (MNA) sowie das Nutritional Risk Screening (NRS) eine ausreichende prädiktive Validität in diesem geriatrischen Patientengut, um ein Screening auf Mangelernährung durchzuführen. Bezüglich möglicher therapeutischer Interventionen ist die Studienlage limitiert: Vorhandene Studien zeigen oft eine geringe Patientenzahl und demente Patienten, die besonders häufig mangelernährt sind, wurden häufig ausgeschlossen. Eine Leitlinie explizit für dieses spezielle Patientengut existiert aktuell nicht. Ein suffizientes Screening des Ernährungszustandes sowie Daten zur Durchführbarkeit und Effizienz einer kurzfristigen perioperativen Nahrungsergänzung könnten einen wichtigen Beitrag zur Stabilisierung dieser oft multimorbiden und fragilen Patienten leisten.
The ecological impacts of invasive species are highly variable and mediated by many factors, including both habitat and population abundance. Lionfish Pterois volitans are an invasive marine species which have high reported detrimental effects on prey populations, but whose effects relative to native predators are currently unknown for the recently colonized eastern Gulf of Mexico. We used functional response (FR) methodology to assess the ecological impact of lionfish relative to 2 functionally similar native species (red grouper Epinephelus morio and graysby grouper Cephalopholis cruentata) foraging in a heterogeneous environment. We then combined the per capita impact of each species with their field abundance to obtain a Relative Impact Potential (RIP). RIP assesses the broader ecological impact of invasive relative to native predators, the magnitude of which predicts community-level negative effects of invasive species. Lionfish FR and overall consumption rate was intermediate to that of red grouper (higher) and graysby grouper (lower). However, lionfish had the highest capture efficiency of all species, which was invariant of habitat. Much higher field abundance of lionfish resulted in high RIPs relative to both grouper species, demonstrating that the ecological impact of lionfish in this region will be driven mainly by high abundance and high predator efficiency rather than per capita effect. Our comparative study is the first empirical assessment of lionfish per capita impact and RIP in this region and is one of few such studies to quantify the FR of a marine predator.
Migratory marine species: their status, threats and conservation management needs