Publications by authors named "Ross Culloch"

In the design of protected areas for cetaceans, spatial maps rarely take account of the life-history and behaviour of protected species relevant to their spatial ambit, which may be important for their management. In this study, we examined the distribution and feeding behaviours of adult versus juvenile minke whales (Balaenoptera acutorostrata) from long-term studies in the Moray Firth in northeast Scotland, where a Marine Protected Area (MPA) has recently been designated. Data were collected during dedicated boat surveys between 2001 and 2022 inclusive, from which 784 encounters with 964 whales of confirmed age-class (471 juveniles and 493 adults) were recorded from 56,263 km of survey effort, resulting in 238 focal follows.

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Marine renewables could form a significant part of the green energy mix. However, a potential environmental impact of tidal energy converters (TECs) is collision risk between a device and animal, which has been a significant barrier in the consenting process. While it is important to understand the number of collisions of an animal with the device, the relative speed at which an animal collides with the device, and the point on the animal where collision occurs, will determine whether a collision is fatal, which is important in understanding population-level impacts.

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The marine renewable energy industry is expanding as countries strive to reach climate targets as set out in the Paris Agreement. For tidal energy devices, the potential risk for animals to collide with a device, particularly its moving parts such as rotor blades, is often a major barrier in the consenting process. Theoretical work surrounding collision risk has commonly made use of a formulaic modelling approach.

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Growing concern about the impacts of anthropogenic noise on marine life has led to a global increase in the number of acoustic monitoring programmes aiming to quantify underwater soundscapes. However, low-frequency measurements in coastal sites may be affected by flow noise that is not actually present in the environment, but is caused by tidal flow turbulence around the hydrophone. At present, there is no standard way of removing this contaminating noise.

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Phylogeographic inference has provided extensive insight into the relative roles of geographical isolation and ecological processes during evolutionary radiations. However, the importance of cross-lineage admixture in facilitating adaptive radiations is increasingly being recognised, and suggested as a main cause of phylogenetic uncertainty. In this study, we used a double digest RADseq protocol to provide a high resolution (~4 Million bp) nuclear phylogeny of the Delphininae.

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This paper presents the first noise measurements of a quarter-scale subsea tidal kite (anchored to the sea floor by a tether and flying in a figure-eight configuration in the water column) operating in field conditions. Challenges in the measurement and post-processing of the data are detailed. Results are presented for three operating conditions of the kite: (1) varying turbine rotations per minute (RPM), (2) varying kite speed, and (3) a twisted tether.

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The mathematical problem of establishing a collision probability distribution is often not trivial. The shape and motion of the animal as well as of the the device must be evaluated in a four-dimensional space (3D motion over time). Earlier work on wind and tidal turbines was limited to a simplified two-dimensional representation, which cannot be applied to many new structures.

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Between-female variation in reproductive output provides a strong measure of individual fitness and a quantifiable measure of the health of a population which may be highly informative to management. In the present study, we examined reproductive traits in female bottlenose dolphins from the east coast of Scotland using longitudinal sightings data collected over twenty years. From a total of 102 females identified between 1997 and 2016, 74 mothers produced a collective total of 193 calves.

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Consistent individual differences (CIDs) in behaviour, indicative of behavioural types or personalities, have been shown in taxa ranging from Cnidaria to Mammalia. However, despite numerous theoretical explanations there remains limited empirical evidence for selective mechanisms that maintain such variation within natural populations. We examined behavioural types and fitness proxies in wild female grey seals at the North Rona breeding colony.

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