Publications by authors named "Roland Proud"
For many species, estimating density is challenging, but it is important for conservation planning and understanding the functional role of species. Bats play key ecological roles, yet little is known about their free-ranging density. We used a long-term banding study of four species caught in an extensively forested climate refuge and spatial capture-recapture models (SCR) to estimate density and its change over time.
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- Seamounts are vital marine habitats with high species diversity, but they are threatened by human activities and are challenging to protect due to their offshore and shallow characteristics.
- Estimates suggest there are between 10,000 and 60,000 seamounts, with recent studies using improved bathymetry data to update these predictions, highlighting the importance of accurate mapping for marine research.
- A survey in the British Indian Ocean Territory revealed issues with previous predictions, revealing 15 'phantom seamounts' that resulted from misinterpretations of navigational charts, showcasing the need for better data quality; the current estimate now stands at 37,889 seamounts, reflecting an increase from earlier counts.
The Arctic marine ecosystem is shaped by the seasonality of the solar cycle, spanning from 24-h light at the sea surface in summer to 24-h darkness in winter. The amount of light available for under-ice ecosystems is the result of different physical and biological processes that affect its path through atmosphere, snow, sea ice and water. In this article, we review the present state of knowledge of the abiotic (clouds, sea ice, snow, suspended matter) and biotic (sea ice algae and phytoplankton) controls on the underwater light field.
View Article and Find Full Text PDFWe provide the raw acoustic data collected from the R/V Hesperides during the global Malaspina 2010 Spanish Circumnavigation Expedition (14th December 2010, Cádiz-14th July 2011, Cartagena) using a Simrad EK60 scientific echosounder operating at 38 and 120 kHz. The cruise was divided into seven legs: leg 1 (14th December 2010, Cádiz-13th January 2011, Rio de Janeiro), leg 2 (17th January 2011, Rio de Janeiro-6th February 2011, Cape Town), leg 3 (11th February 2011, Cape Town-13th March 2011, Perth), leg 4 (17th March 2011, Perth-30th March 2011, Sydney), leg 5 (16th April 2011, Auckland-8th May 2011, Honolulu), leg 6 (13th May 2011, Honolulu-10th June 2011, Cartagena de Indias) and leg 7 (19th June 2011, Cartagena de Indias-14th July 2011, Cartagena). The echosounder was calibrated at the start of the expedition and calibration parameters were updated in the data acquisition software (ER60) i.
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- Projecting the effects of climate change on Arctic marine food webs and fisheries is complex because of the close ties between biology and ice conditions.
- A food web model called StrathE2EPolar was used to simulate how climate change impacts fisheries in the Barents Sea, based on predictions from the NEMO-MEDUSA climate model.
- By the 2040s, the Barents Sea is expected to be over 95% ice-free year-round and about 2°C warmer, leading to increased productivity for demersal fish like cod and haddock, but decreased reference points for planktivorous fish, creating challenges for ecosystems and fisheries management.
The global ocean's near surface can be partitioned into distinct provinces on the basis of regional primary productivity and oceanography [1]. This ecological geography provides a valuable framework for understanding spatial variability in ecosystem function but has relevance only partway into the epipelagic zone (the top 200 m). The mesopelagic (200-1,000 m) makes up approximately 20% of the global ocean volume, plays important roles in biogeochemical cycling [2], and holds potentially huge fish resources [3-5].
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