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Purpose: The Manx shearwater flea Ceratophyllus (Emmareus) fionnus Usher, 1968 is a host-specific parasitic insect apparently restricted to the Isle of Rùm, off the west coast of Scotland. Although C. (E.) fionnus is one of only a small number of insect species endemic to the British Isles, its conservation status has never been evaluated. To enable effective management, the conservation status of the species was assessed. Methods: The conservation status of C. (E.) fionnus was evaluated using host and distribution records in conjunction with two assessment rubrics; the IUCN Red List Categories and Criteria: Version 3.1, and a flea-specific assessment rubric developed previously. Results: Ceratophyllus (Emmareus) fionnus was found to be threatened with extinction due to its hyperendemicity on the Isle of Rùm and was classified as vulnerable. Conclusion: Based on the findings of the assessment, immediate conservation action to protect C. (E.) fionnus is encouraged and a recovery plan is outlined. This includes surveys and studies of the bionomics of the species in conjunction with in-situ management of the known population. The creation of insurance populations through conservation translocations is also encouraged. [ABSTRACT FROM AUTHOR]

Abstract: Demographic senescence is increasingly recognised as an important force shaping the dynamics of wild vertebrate populations. However, our understanding of the processes that underpin these declines in survival and fertility in old age remains limited. Evidence for age‐related changes in foraging behaviour and habitat use is emerging from wild vertebrate studies, but the extent to which these are driven by within‐individual changes, and the consequences for fitness, remain unclear. Using longitudinal census observations collected over four decades from two long‐term individual‐based studies of unmanaged ungulates, we demonstrate consistent within‐individual declines in home range area with age in adult females. In both systems, we found that within‐individual decreases in home range area were associated with increased risk of mortality the following year. Our results provide the first evidence from the wild that age‐related changes in space use are predictive of adult mortality. [ABSTRACT FROM AUTHOR]

ABSTRACT Hunting is a common component in the management of ungulate species. Despite its widespread use, the influence of selective harvesting on phenotypic trait change is still ambiguous, and represents a critical gap in our understanding of the responses of wild populations under harvest. Using the long-term red deer ( Cervus elaphus) dataset (1972-2012) from the Isle of Rum National Nature Reserve, Scotland, we assessed the relationship between antler length and key demographic processes (i.e., survival, recruitment, antler growth, parent-offspring trait correlation) for the male component of the population. We then constructed the first integral projection model for this species to examine the effects of simulated trophy hunting on 2 population-level parameters: the stable antler size distribution and the relative reproductive value of males. When male mortality rates due to hunting were <20%, the effect on antler size distribution and the reproductive value function were relatively small. However, as mortality due to hunting increased to 50% in large individuals, the direct effects of hunting on mean antler size and reproductive value became evident. Our model acts as a useful starting point to investigate the ecological and evolutionary consequences of hunting in red deer. © 2016 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Temporal changes in phenological traits arising as a consequence of recent rapid environmental change have been widely demonstrated in animal populations. Increasingly, studies are seeking to understand the impact of changes in such traits on individual fitness and population dynamics, with the ultimate aim of predicting population persistence or extinction under different climate scenarios. Here, we examined the effects of environmental change on maternal reproductive traits in a wild population of red deer (Cervus elaphus) and sought to explain why, despite a rapid advance in offspring birth dates, we observed no apparent consequences for offspring fitness. By using path analysis, we identified both direct and indirect paths along which changes in environmental conditions affected birth date, birth mass, juvenile survival, and female fecundity. In general, warmer temperatures were associated with earlier birth dates and greater birth mass, and higher rainfall was associated with reduced juvenile survival and reduced female fecundity. We also examined concurrent effects of population density, maternal age, and reproductive history, and found that temporal stasis in average trait values, at least in part, could be explained by antagonistic roles of direct and indirect effects of changing climate and increasing population density. Identification of the many mechanisms that contribute to the dynamics of phenotypic traits is challenging; this study demonstrates the need to consider both climatic and demographic variation in order to understand the fitness consequences of changes in phenological traits. [ABSTRACT FROM AUTHOR]

The Rum Igneous Centre comprises two early marginal felsic complexes (the Northern Marginal Zone and the Southern Mountains Zone), along with the later central ultrabasic-basic layered intrusions. These marginal complexes represent the remnants of near-surface to eruptive felsic magmatism associated with caldera collapse, examples of which are rare in the North Atlantic Igneous Province. Rock units include intra-caldera collapse breccias, rhyolitic ignimbrite deposits and shallow-level felsic intrusions, as well the enigmatic 'AmMàm intrusion breccia'. The latter comprises a dacitic matrix enclosing lobate basaltic inclusions (∼1-15 cm) and a variety of clasts, ranging from millimetres to tens of metres in diameter. These clasts comprise Lewisian gneiss, Torridonian sandstone and coarse gabbro. Detailed re-mapping of the Am Màm intrusion breccia has shown its timing of emplacement as syn-caldera, rather than pre-caldera as previously thought. Textural analysis of entrained clasts and adjacent, uplifted country rocks has revealed their thermal metamorphism by early mafic intrusions at greater depth than their present structural position. These findings provide a window into the evolution of the early mafic magmas responsible for driving felsic magmatism on Rum. Our data help constrain some of the physical parameters of this early magma-crust interaction and place it within the geochemical evolution of the Rum Centre. [ABSTRACT FROM AUTHOR]

Sr and Nd isotope ratios, together with lithophile trace elements, have been measured in a representative set of igneous rocks and Lewisian gneisses from the Isle of Rum in order to unravel the petrogenesis of the felsic rocks that erupted in the early stages of Palaeogene magmatism in the North Atlantic Igneous Province (NAIP). The Rum rhyodacites appear to be the products of large amounts of melting of Lewisian amphibolite gneiss. The Sr and Nd isotopic composition of the magmas can be explained without invoking an additional granulitic crustal component. Concentrations of the trace element Cs in the rhyodacites strongly suggests that the gneiss parent rock had experienced Cs and Rb loss prior to Palaeogene times, possibly during a Caledonian event. This depletion caused heterogeneity with respect to 87Sr/86Sr in the crustal source of silicic melts. Other igneous rock types on Rum (dacites, early gabbros) are mixtures of crustalmelts and and primarymantle melts. Forward Rare Earth Element modelling shows that late stage picritic melts on Rum are close analogues for the parent melts of the Rum Layered Suite, and for the mantle melts that caused crustal anatexis of the Lewisian gneiss. These primary mantle melts have close affinities to Mid-Oceanic Ridge Basalts (MORB), whose trace element content varies from slightly depleted to slightly enriched. Crustal anatexis is a common process in the rift-to-drift evolution during continental break-up and the formation of Volcanic Rifted Margins systems. The 'early felsic-later mafic' volcanic rock associations from Rum are compared to similar associations recovered from the now-drowned seaward-dipping wedges on the shelf of SE Greenland and on the Vøring Plateau (Norwegian Sea). These three regions show geochemical differences that result from variations in the regional crustal composition and the depth at which crustal anatexis took place. [ABSTRACT FROM AUTHOR]

The Western Granite is the largest of several granitic bodies around the margin of the Rum Central Igneous Complex. We report palaeomagnetic and anisotropy of magnetic susceptibility (AMS) data that bear on the emplacement and deformation of the Western Granite. The collection includes samples from 27 sites throughout the Western Granite, five sites in adjacent feldspathic peridotite, and two sites in intermediate to mafic hybrid contact aureole rocks. Palaeomagnetic data from 22 of the 27 sites in the granite provide an in situ group mean D = 213.2°, I=-69.5°, α95 = 5.5° that is discordant to an early Paleocene reverse polarity expected field (about 184°, -66°, α95 = 4.3°). The discrepancy is eliminated by removing an inferred 15° of northwest-side-down tilting about a best fit horizontal tilt axis trending 040°. Data from the younger peridotite and hybrid rocks of the Rum Layered Suite provide an in situ group mean of D = 182.6°, I = -64.8°, α95 = 4.0°, which is statistically indistinguishable from an early Paleocene expected field, and imply no post-emplacement tilting of these rocks since remanence acquisition. The inferred tilt recorded in the Western Granite, which did not affect the younger Layered Suite, suggests that emplacement of the ultrabasic rocks resulted in roof uplift and associated tilt of the Western Granite to make space for mafic magma emplacement. Magnetic fabric magnitude and susceptibility parameters yield two subtle groupings in the Western Granite AMS data set. Group 1 data, defined by rocks from exposures to the east and south, have comparatively high bulk susceptibilities (Kmean, 29.51 × 10-3 in SI system), stronger anisotropies (Pj, 1.031) and oblate susceptibility ellipsoids. Group 2 data, from rocks in the west part of the pluton, have lower values of Kmean (15.89 × 10-3 SI) and Pj (1.014), and triaxial susceptibility ellipsoids. Magnetic lineations argue for emplacement of the granite as a tabular sheet from the south-southeast toward the north and west. Moderate to steeply outward-dipping magnetic foliations, together with deflection of the country rock bedding in the north, are consistent with doming accompanying magma emplacement. [ABSTRACT FROM AUTHOR]

The Southern Mountains Zone of the Rum Central Complex lies inside a major ring fault and comprises an intricate association of country-rock outcrops, breccias and rhyodacite. The breccias and rhyodacite were long thought to be products of subterranean explosion and intrusion, respectively. Here, we report new observations that support re-interpretation of these units as mass movement deposits and ignimbrites. The most abundant breccias (Coire Dubh-type) consist mainly of countryrock clasts < 1 m in diameter in a sand or silt matrix. Internally bedded and graded, and interlayered with sandstones and lithic tuffs, these breccias are interpreted as debris flow and stream flow deposits. Rhyodacite sheets show gradational or sharp, concordant contacts with Coire Dubh-type breccias, and display graded basal lithic tuffs and graded fiamme swarms. These sheets are interpreted asmoderately to densely welded rhyodacite ignimbrites (25-100 m thick). A steep body of fragmented (fiammebearing) rhyodacite with intrusive non-fragmented contacts is interpreted as an ignimbrite vent system. The rhyodacite and breccia succession is over 200 m thick and unconformably overlies a structurally uplifted Precambrian basement, within which there is also evidence of later subsidence. Outcrops of potential caldera-collapse 'megabreccia' are more structurally consistent than previously thought, and are re-interpreted here as coherent segments of Precambrian country rock (caldera floor). The Southern Mountains Zone breccias and rhyodacites respectively reflect sedimentary and pyroclastic processes acting in response to a complex tectonic interplay of intrusion-related uplift and caldera subsidence. [ABSTRACT FROM AUTHOR]

Abstract: Earthworm surveys were conducted on the Isle of Rum (NNR), Inner Hebrides, Scotland. Fifteen species were located representing all three ecological groups of earthworm. Most species have a very limited distribution, around current or former centres of human habitation and are associated with anthropic activity. Bulk addition of mainland soil at Kinloch provided conditions that now support 12 species (greatest diversity recorded). Three species Dendrodrilus rubidus, Dendrobaena octaedra, and Lumbricus rubellus are almost ubiquitous across Rum, occurring on acidic moorland and to the summit of the highest peak (812 m). Fertiliser addition at such altitude to patchy, herb-rich Calluna heath, has led to greater earthworm numbers but no more species. Where woodland has been re-established on moorland, earthworm communities showed significantly increased numbers (up to 170 m–2 with a mass of 25 g m–2) and increased diversity compared with associated moorland (approximately 10 m–2). It is suggested that selected earthworms, such as Aporrectodea caliginosa and L. rubellus may have a role in assisting soil development and woodland establishment, so their use in the continuing Rum afforestation programme ought to be considered. [Copyright &y& Elsevier]

A change in population density can generate spatial and demographic effects that can have an impact on fluctuations in population size for many years. Although the demographic effects of tithe lags have been incorporated into analyses of time series data, there are few detailed descriptions of the long-term demographic consequences of a change in density. We use detailed, individual-based data from a population of red deer (Cervus elaphus) from the North Block of the Isle of Rum, Scotland, to describe long-term demographic and spatial effects of a change in density. The population was released from hunting pressure in 1972. Over the following 10 years population density doubled and, since the early 1980s, has fluctuated around ecological carrying capacity. The cessation of culling led to long-term transient spatial and demographic effects that have persisted for 30 years. Different vital rates responded to the increase in density at different rates, causing long-term changes to the demographic and spatial structure of the population. These changes altered the impact of different age- and sex-specific vital rates on annual changes in population size. These changes are still ongoing, 30 years after cessation of the cull, suggesting that a change in density may generate transient dynamics that persist for several generations. [ABSTRACT FROM AUTHOR]