Nomadic Movements Research Articles

Wintering ecology and nomadic movement patterns of Short-eared Owls Asio flammeus on a subtropical island

ABSTRACTCapsule: Short-eared Owls Asio flammeus showed a female-biased sex ratio in their southernmost wintering grounds in Oriental Asia. This is the first description of a nomadic movement pattern in this area.Aims: To investigate the sex ratio, movement patterns, home range size and habitat preference of non-breeding Short-eared Owls in subtropical Taiwan.Methods: Eleven Short-eared Owls were radio tracked following trapping and transportation away from an airport as part of the management of bird-strike risk for aeroplanes.Results: Our results indicated a female-skewed (75%) sex ratio for Short-eared Owls wintering in Taiwan. The owls demonstrated a nomadic behaviour by showing a repetitive pattern of high roosting site fidelity in the short term, followed by a long-distance movement to a different discrete area. Grasslands were commonly used as day-roosting sites but agricultural habitats were favoured at night.Conclusion: Compared to on the breeding ground, the wintering owls exhibited a much larger home range size and exploit more dispersed patches of suitable habitats. These results revealed a notable conservation issue for the wintering owls, especially in the degraded and partially developed landscapes in subtropical countries.

Neolithic nomadism in south‐east Arabia — strontium and oxygen isotope ratios in human tooth enamel from al‐Buhais 18 and Umm al‐Quwain 2 in the Emirates of Sharjah and Umm al‐Quwain (UAE)

Human skeletal remains from the Neolithic sites BHS18 in the interior of the Sharjah Emirate and the Neolithic shell midden UAQ2 (Umm al‐Quwain) on the coast of the Persian Gulf (United Arab Emirates, UAE) were analysed for their isotope ratios of strontium (87Sr/86Sr) and oxygen (18O/16O). The results are not in agreement with earlier assumptions about a Neolithic nomadism between inland regions and the south‐eastern coast of the Persian Gulf. Existing evidence of nomadic movements of the people from BHS18 most possibly refers to transhumance within the mountains in the hinterland. The strontium isotope measurements on human skeletons from UAQ2 on the contrary indicate uninterrupted residence of this population on the coast. Nevertheless, evidence was found of individual mobility between inland regions and the coast.

After Dada: Fluxus as a Nomadic Art Movement

In this article Stephen Wilmer applies Deleuze and Guattari's concept of nomadology to the Fluxus art movement that spread across the world, breaking down barriers between art and life, privileging concrete and conceptual art, and staging unusual events. He traces Rosi Braidotti's development of Deleuze and Guattari's concept into her notion of the nomadic subject in which she favours factors such as geographic movement, transnational identities, common space (in accord with the Deleuzian differentiation between the divisible earth or private property, and nomadic space which belongs to everyone), polylingualism, desubjectivation, becoming minoritarian, and thinking and acting differently. With this as a philosophical and political context, the author investigates some of the artistic practices of specific Fluxus practitioners, especially the shamanistic performances and fat and felt installations of Joseph Beuys that supposedly owed their inspiration to his experience with nomadic Tatars. Stephen Wilmer is Professor Emeritus of Drama at Trinity College Dublin. He co-edited (with Audronė Žukauskaitė) Resisting Biopolitics: Philosophical, Political, and Performative Strategies (Routledge, 2016) and Deleuze and Beckett (Palgrave Macmillan, 2015). He edited ‘Theatre and the Nomadic Subject’ for Nordic Theatre Studies (2015), and co-edited (with Azadeh Sharifi) ‘Theatre and Statelessness in Europe’ for Critical Stages (2016).

Breeding site sampling across the Arctic by individual males of a polygynous shorebird.

Males of many polygynous species compete for access to fertile females without providing them with resources other than sperm and without investing in care for the offspring (male dominance polygyny). In such systems, local competition for access to females is intense and typically only a few males obtain matings, leading to strong sexual selection. Sampling multiple breeding areas could then provide a mechanism for males to increase their chances to reproduce. However, little is known about such sampling behaviour and about the spatial scale at which males compete. Here we show that most males of a migratory, polygynous shorebird, the pectoral sandpiper (Calidris melanotos), that arrived at a known breeding location in northern Alaska subsequently moved through a considerable part of the entire species' breeding range (up to 13,045 km in a four-week period), sampling as many as 23 additional potential breeding sites. Our data suggest that males do not have a final breeding destination after migration from their wintering quarters, but make nomadic movements that are probably not a consequence of breeding failure. Tenure, the duration of stay at a site, correlated strongly with the number of breeding females at the site, suggesting that decisions to leave are dependent on local mating opportunities. Nomadic movements may allow males to display and sire offspring at multiple sites within a single breeding season. Sexual selection may then favour high-performance males that are able to reduce sleep to compete locally and to fly long distances between breeding sites, leading to a population with unrestricted interbreeding and without local adaptation and speciation.

Spatiotemporal habitat dynamics of ungulates in unpredictable environments: The khulan (Equus hemionus) in the Mongolian Gobi desert as a case study

In resource-poor environments many large herbivores do not perform seasonal migrations but show unpredictable, long-range movements within a given season. The few studies that have examined drivers for within season long-range movements suggest that these movements are a response to spatiotemporal dynamics of foraging resources.We tested this hypothesis and were especially interested in detecting dynamics of foraging habitat which may influence high mobility of khulan, Equus hemionus, during summers in the Dzungarian Gobi of Mongolia. We used six years of ground census data combined with remotely sensed imagery of vegetation productivity (NDVI) to build a dynamic habitat model. We subsequently predicted khulan habitat suitability for each of the seven 16-day NDVI intervals every summer between 2004 and 2009 and examined variability of the resulting 42 prediction maps to characterize spatiotemporal dynamics in khulan foraging habitat.Our analyses showed khulan summer foraging habitat was highly predictable with little spatiotemporal variability making it unlikely that broad scale variability of foraging habitats can explain the high mobility of khulan. The few and small areas that did show khulan habitat variability were related to locations around water sources. In addition, we found that khulan avoided habitats beyond 21km from water sources. Together these findings suggest that water availability and switching among the sparsely located water bodies rather than broad scale dynamics of foraging habitats may be the key driver for the high mobility of khulan in the Dzungarian Gobi. Our findings highlight the importance of securing access to and connectivity among water bodies for wild ungulates and the need for further studies on possible drivers of nomadic movements in drylands.

Ungulate movement in an extreme seasonal environment: year‐round movement patterns of high‐arctic muskoxen

Detailed knowledge on movement behaviour of free‐ranging muskoxen Ovibos moschatus is currently lacking. Quantifying variation in individual movement and the variables driving such patterns is important to understand how they meet their basic requirements and to inform management. Because muskoxen exist in nutrient‐poor systems with extreme climatic and seasonal variability, individual movement patterns are expected to be largely dependent on environmental conditions and the seasonal variation therein. We analysed high‐resolution location data of 14 adult female muskoxen roaming around Zackenberg in northeast Greenland (74°28′N, 20°34′W). We assessed the relative importance (Akaike variable weights) of multiple extrinsic conditions in explaining variation in hourly speed, turning angles, and activity. We found that time of day, ambient temperature, and land cover types were the most important covariates explaining variation in fine‐scale movement and activity patterns throughout the year. Movement speeds were consistently lower in land cover types with more dense vegetation. Speed of movement was positively correlated with ambient temperature when the days were long, while negatively related with temperature in periods with few or no hours of daylight. Diurnal peaks in movement and activity patterns were observed most of the year (including mid‐winter months with 24‐h darkness), except during high‐summer (24‐h of daylight), when individual movement and activity remained continuously high. The topographic variation (elevation and slope) explained only a small part of the variation in muskox movement patterns in the areas where the muskoxen were observed. Analyses of displacement patterns revealed a mixture of movement behaviours. We conclude that muskoxen in high‐arctic Greenland adopt a largely nomadic movement behaviour, but do so within a rather small geographical area (app. 5000 km2), and that their movement and activity patterns are largely directed at finding suitable foraging patches and avoiding cold‐stress during harsh winter weather.

Community ecology of the metazoan parasites of snoek Thyrsites atun (Euphrasen, 1791) (Perciformes: Gempylidae) off South Africa

The parasite assemblage of snoek Thyrsites atun, a commercially important fish in the Benguela system, was examined over a one-year period. In all, 16 parasite taxa including eight new host records (Bolbosoma vasculosum, Caligus coryphaenae, Caligus dakari, Corynosoma australe, Hatschekia conifera, Nothobomolochus fradei, Rhadinorhynchus cadenati, Tentacularia coryphaenae) and four new locality records (B. vasculosum, C. dakari, Molicola uncinatus, Pseudoterranova sp.) were recovered from 210 specimens. The dominance of larval helminths in the component community suggests that T. atun occupies an intermediate position in the food web. The ‘nestedness metric based on overlap and decreasing fill’ (NODF) indicated that the parasite assemblage exhibited no nestedness (NODF = 73.3, p = 0.103). Generalised additive mixed modelling results indicated that host length is the main determinant of parasite species richness in T. atun. PERMANOVA and ANOSIM suggested that infracommunity structure varied little with respect to the sex, length, seasonality and capture region of the host. The stability and randomness in parasite acquisition, as indicated by the lack of nestedness of the parasite assemblage, can be ascribed to the opportunistic feeding behaviour and nomadic movement of T. atun in the southern Benguela. The homogeneity of the community structure of long-lived endoparasites suggests that a single T. atun stock occurs off South Africa.

Musical Bodies: Corporeality, Emergent Subjectivity, and Improvisational Spaces

Interactive improvisational musical spaces (which is to say, nearly all musical spaces) involve affective relations among bodies: between the bodies of human performers, between performers and active listeners, between the sonic "bodies" that comprise the multiple overlapping events that constitute a musical performance’s unfolding. Music scholarship tends to focus on either music’s sonic materialities (the sensible; what can be heard) or the cultural resonances that locate in and through music (the political or hermeneutic; how meaning is inscribed in and for a listening subject). An embodied turn, however, has recently been manifesting, bringing music scholarship into communication with feminist theory, queer theory, and approaches that foreground subjectivity and embodiment. Exemplary in this area are works by Naomi Cumming (who asks a critical question, “does the self form the sound, or the sound the self?;” Cumming 7), Suzanne Cusick, Marion Guck, Fred Maus, and Susan McClary. All of these scholars, in various ways, thematise the performative—what it feels like to make or experience music, and what effect that making or experiencing has on subject-formation. All of these authors strive to foreground the role of the performer and performativity in the context of the extended Western art music tradition. While each makes persuasive, significant points, my contention in this paper is that improvised music is a more fruitful starting place for thinking about embodiment and the co-constitutive relationship between performer and sound. That is, while (nearly) all music is improvised to a greater or lesser degree, the more radical contexts, in which paths are being selected and large-scale shapes drawn in the “heat of the moment,” can bring these issues into stark relief and serve as more productive entry points for thinking through crucial questions of embodiment, perspective, identity, and emergent meaning.

The Arctic Nomads: Strategies of Mobility

The research focuses on Chukotka, Yamal and Kola peninsulas––the three source areas of Arctic reindeer breeding nomadism. The method of movement recording, termed TMA (tracking–mapping–acting), reveals a multidimensional pattern of nomadic movement with peaks and pauses, personal and social trajectories. The comparison of tracks shows that in contrast to ordinary reindeer herders, the leaders perform more complex and extended maneuvers for surveying vicinities, evaluating the situation, and specifying next steps. Three “close-ups” demonstrate their dense activity patterns covering natural and social environment and ensuring control over territory, reindeer, the nomadic community, external contacts, and threat prevention. In terms of spatial control and movement, herders practice different styles such as “circular” (Chukotka), “migratory” (Yamal), and “fenced” (Kola). In all three tundras, key roles belong to infl uential leaders whose experience and energy, by local people’s belief, are the backbone of reindeer herding. In turn, the leaders argue that husbandry is ineffi cient without authoritarian control, although they widely use social (including kin) ties in their strategies. Nomads and their leaders rely upon traditions but are open to innovations. Reindeer symbolize the identity of Arctic nomadic cultures since herding provides autonomy in subsistence, movement, and communication. However, traditional technologies of life-in-motion can be seen as valuable resource for present-day Arctic strategies.

Distribution and diversity of the vectors of Rift Valley fever along the livestock movement routes in the northeastern and coastal regions of Kenya.

BackgroundKnowledge of vector ecology is important in understanding the transmission dynamics of vector borne disease. In this study, we determined the distribution and diversity of mosquitoes along the major nomadic livestock movement routes (LMR) in the traditional pastoral ecozone of northeastern Kenya. We focused on the vectors of Rift Valley fever virus (RVFv) with the aim of understanding their ecology and how they can potentially influence the circulation of RVFv.MethodsMosquito surveys were conducted during the short and long rainy seasons from November 2012 to August 2014 using CO2-baited CDC light traps at seven sites selected for their proximity to stopover points that provide pasture, water and night bomas (where animals spend nights). We compared mosquito abundance and diversity across the sites, which were located in three ecological zones (IV, V and VI), based on the classification system of agro-ecological zones in Kenya.ResultsOver 31,000 mosquitoes were trapped comprising 21 species belonging to 6 genera. Overall mosquito abundance varied significantly by ecological zones and sites. Mansonia species (Ma. uniformis and Ma. africana) were predominant (n = 12,181, 38.3 %). This was followed by the primary RVF vectors, Ae. ochraceus and Ae. mcintoshi comprising 17.9 and 14.98 %, respectively, of the total captures and represented across all sites and ecological zones. The Shannon diversity index ranged from 0.8 to 2.4 with significant zone, site and seasonal variations. There was also significant species richness of RVF vector across ecological zones.ConclusionOur findings highlight differential occurrence of RVFv vectors across ecological zones and sampling sites, which may be important in determining areas at risk of emergence and circulation of RVFv. Moreover, the vector distribution map along LMR generated in this study will guide potential interventions for control of the disease, including strategic vaccination for livestock.

The Spirit of Fluxus as a Nomadic Art Movement

Fluxus was the brain-child of a Lithuanian-born artist named George Maciunas whose family fled to Germany in the Second World War, where they eventually became displaced persons and later emigrated to the USA. Maciunas studied art and architecture in Pittsburgh and New York before working as an architect and graphic artist and founded the Fluxus movement at the beginning of the 1960s. During his student years, he became fascinated by nomadic art in Asia and Eastern Europe that would later influence his life’s work. This essay considers the relationship between his interest in nomadism and the nature of the Fluxus movement that spread across the world, breaking down barriers between art and life, privileging concrete and conceptual art, and staging unusual events. It applies Braidotti’s notion of the nomadic subject to Maciunas’ encouragement of radical styles of performance art, such as Yoko Ono’s minimalist conceptual work and Joseph Beuys’s Tatar-influenced use of fat and felt.

Occurrence of rift valley fever in cattle in Ijara district, Kenya

Ijara district in Kenya was one of the hotspots of rift valley fever (RVF) during the 2006/2007 outbreak which led to human and animal deaths causing huge economic and public health losses. The main constraint in the control and prevention of RVF is inadequate knowledge on its occurrence during the interepidemic period. This study was aimed at understanding the occurrence of RVF in cattle in Ijara to enable the development of improved community-based disease surveillance, prediction, control and prevention.Six herds each 700–1000 cattle were identified with participatory involvement of locals and project technical team of the project. One animal per herd was tagged with global position system (GPS) collar to enable follow up. Sero-surveys were conducted periodically to understand the herd's movement through various ecological zones and risk of exposure to RVF virus. Sixty animals less than 3 years old from each herd were randomly selected each sampling time and sero-surveyed for RVF four times (September 2012, December 2012, February 2013 and May 2013) during the study period and along the nomadic movement route. The serum samples collected were subjected to RVF inhibition ELISA test to detect if there was exposure for RVF virus (RVFV). The RVF inhibition ELISA positive samples were subjected to IgM ELISA test to determine if the exposures were current or recent (within 14 days).The result of the survey indicated that 13.1% (183/1396) of cattle sero-surveyed had RVFV antibodies by inhibition ELISA test while 1.4% (18/1396) was positive for IgM ELISA test. The highest RVFV circulation was detected after herds pass through bony forest between Lamu and Ijara and Halei forested areas. These forested areas also had the highest IgM detections. The findings indicate that even limited rainfall was able to initiate RVFV circulation in Ijara region with highest circulation detected within forested areas with potential to become epidemic if rains persist with extensive flooding. There is need to carry out regular participatory disease surveillance in domestic animals and other host systems to identify risk locations in hotspot areas and carry out community awareness and focal vaccination campaigns against RVF for preparedness, prevention and control. Additionally, monitoring of environmental conditions in risky ecological zones to detect enhanced rainfall and flooding should be prioritized for preparedness.

Hepatitis E in Karamoja, Uganda, 2009-2012: epidemiology and challenges to control in a setting of semi-nomadic pastoralism.

A prolonged hepatitis E outbreak occurred between 2009 and 2012 among a semi-nomadic pastoralist population in the Karamoja region of Uganda. As data on the public health problems of nomadic pastoralists in sub-Saharan Africa is limited, we sought to characterize the epidemiology and challenges to control of hepatitis E in such a setting. A retrospective case-series investigation was undertaken. Surveillance line-lists of suspected hepatitis E cases maintained during the outbreak were analyzed. Standardized interviews and focus group discussions were conducted with key informants involved in outbreak control activities. Between August 2009 and September 2012, 987 hepatitis E cases with individual case-based data were identified. Of 22 total deaths, almost half occurred during the first 4 months of the outbreak. Infection attack rates were higher among males and young adults. The average time between onset of jaundice and presentation was approximately 1 week. Challenges to control were related to persistent consumption of untreated water, poor sanitation infrastructure, remote geography, nomadic movement and civil insecurity. The hepatitis E outbreak in Karamoja highlights the emergence of sanitation and hygiene-related disease among semi-nomadic pastoralist populations. Improving sanitation and safe water access and extending health education programs to remote pastoralist communities is crucial to prevent such diseases from becoming endemic.

Conserving mobile species

The distributions of many species are dynamic in space and time, and movements made by individuals range from regular and predictable migrations to erratic, resource‐driven nomadism. Conserving such mobile species is challenging; the effectiveness of a conservation action taken at one site depends on the condition of other sites that may be geographically and politically distant (thousands of kilometers away or in another jurisdiction, for example). Recent work has shown that even simple and predictable linkages among sites caused by “to‐and‐fro” migration can make migratory species especially vulnerable to habitat loss, and substantially affect the results of conservation prioritizations. Species characterized by more erratic or nomadic movements are very difficult to protect through current conservation planning techniques, which typically view species distributions as static. However, collaborations between migration ecologists, conservation planners, and mathematical ecologists are paving the way for improvements in conservation planning for mobile species.

Modelling the impacts of marine protected areas for mobile exploited fish populations and their fisheries: what we recently learnt and where we should be going

Marine protected areas (MPAs) are increasingly being considered and used for the management of fisheries targeting mobile fish populations. Here, the recent modelling literature on MPA effects for mobile fish populations and their fisheries is reviewed. Modelling studies conducted since 2011 have filled a considerable number of knowledge gaps on the impacts of MPAs for species exhibiting home-range behaviour, nomadic movements or behavioural polymorphism, and on the effects of “targeted MPAs”, which aim to protect relatively small areas where migratory fishes spend an inordinate fraction of time or are highly vulnerable to fishing (e.g., nursery or spawning zones). Also, in recent years, two studies investigated the consequences of MPAs targeting highly migratory (tuna-like) fish populations for the first time in the history of MPA modelling. Recent modelling studies found that MPAs aimed at protecting mobile species may have positive conservation effects under a relatively wide range of situations, but may generate long-term fisheries benefits only under a very limited set of conditions. In particular, MPAs were not found to be beneficial for the fisheries targeting highly migratory populations. Strategies producing both conservation and fisheries benefits were identified, which depend on fish movement patterns and numerous aspects of fish life history and fisheries dynamics. However, in view of the diversity of fish movement patterns in MPA systems and current dynamics in resource management, it is clear that additional modelling work is needed to fully understand how protected areas affect mobile fish populations and their fisheries and to be able to implement pertinent MPAs. In particular, future modelling studies should systematically assess the effects of MPAs in relation to other management tools to find strategies that are most effective in meeting management objectives, and explore the impacts of “dynamic” MPAs that follow highly migratory fish populations in space and time.

Nomadic beekeeper movements create the potential for widespread disease in the honeybee industry.

To examine the nomadic movements of Australian beekeepers and determine their potential to assist the spread of pests and diseases. A questionnaire was mailed to all beekeepers in Australia who maintained >100 hives, requesting information on the location of their home base, locations used throughout the year and the crops that the bees fed on in each location. The information was analysed using network analysis software and a geographic information system. Nomadic Australian beekeepers formed a connected network linking 288 locations from central Queensland to western Victoria. A second, smaller network included 42 locations in south-eastern South Australia. Almond orchards in Robinvale and Boundary Bend and lucerne seed production in Keith were locations of major hive congregations driven by the opportunity to provide paid pollination services. In the 3 months after completion of almond pollination in August 2008, movement of hives occurred from Robinvale and Boundary Bend to 49 locations, ranging from south-east Queensland to south-west Victoria. The movements identified in this study highlight the potential for rapid spread of disease or pests throughout the beekeeping industry should an incursion occur.

Nomadism and seasonal range expansion in a large frugivorous bird

Studies on the ranging behaviour of birds often suggest that ranges vary seasonally with larger ranges in the non‐breeding compared to the breeding season. However, due to limitations in tracking methods very little is known about the underlying processes driving seasonal differences in ranging behaviour, especially in fragmented, heterogeneous landscapes. Such knowledge is particularly important if movements deliver essential ecosystem functions such as seed dispersal. We contrasted the daily ranging behaviour between the breeding and non‐breeding season of a frugivorous bird and demonstrate how larger seasonal ranges in the non‐breeding season emerge through switching from a stationary home range behaviour to nomadism. We tracked movements of 29 male trumpeter hornbills Bycanistes bucinator across a fragmented landscape of eastern South Africa during different breeding and non‐breeding seasons using high temporal resolution GPS data‐loggers. Birds in the breeding seasons showed a typical, stationary home range pattern. In the non‐breeding seasons birds, rather than expanding their stationary daily ranges, switched to nomadic movements that were characterized by shifts of the general location of daily ranges to a different area every couple of days. We also found that during the breeding seasons hornbills were mostly located in large continuous forests; birds in the non‐breeding seasons frequently used forest patches within the agricultural landscape and residential areas. These seasonal differences in the movement behaviour of trumpeter hornbills may have important consequences for seed dispersal of plant species. Our findings show how seasonal range expansion of frugivorous birds may be driven by fundamental behavioural changes that have important consequences for ecosystem processes.

Temporal Fluctuations in Raptor Abundances in Grasslands of Southeastern South America

Abstract We conducted 44 roadside surveys on grasslands landscapes of southern Brazil and Uruguay to study temporal changes in raptor abundance. Each route was surveyed twice in fall/winter and twice in spring/summer. Raptor abundance was higher during summer than winter, but did not differ between years. Thirteen of the 33 species recorded showed temporal changes in abundance, or are known to be migrants in the region. White-tailed Kite (Elanus leucurus), Yellow-headed Caracara (Milvago chimachima) and Southern Caracara (Caracara plancus) had higher abundance during fall/winter than spring/summer, which might be attributed to nomadic movements in agricultural landscapes. Changes in abundance of Savanna Hawk (Buteogallus meridionalis) and American Kestrel (Falco sparverius) suggest irruptive or nomadic movements. Turkey Vulture (Cathartes aura), Snail Kite (Rostrhamus sociabilis) and White-tailed Hawk (Geranoaetus albicaudatus) were more abundant in spring/summer than fall/winter, and our results suggest ...

Assessing the status and conservation priorities of the short‐eared owl in North America

AbstractThe North American Breeding Bird Survey, Christmas Bird Count, and regional and national conservation assessments provide convincing evidence that the short‐eared owl (Asio flammeus) is experiencing a range‐wide, long‐term decline in abundance in North America. However, the species has received little conservation or research attention. The short‐eared owl is vulnerable to decline because it relies heavily on large, intact grasslands and a specialized diet of unpredictable small mammal prey. The species' nomadic movements compound these vulnerabilities by making a decline difficult to detect with current monitoring programs while obfuscating stewardship responsibilities for managers. The primary threat to the species is loss, fragmentation, and degradation of large tracts of native grasslands and wetlands. We propose the following conservation priorities to better understand and begin addressing the short‐eared owl's decline: 1) better define and protect important habitats; 2) improve population monitoring; 3) determine seasonal and annual movements; 4) re‐evaluate NatureServe's short‐eared owl national conservation classifications; 5) develop management plans and tools; and 6) classify raptors, including short‐eared owls, as migratory birds in Canada. We contend that the short‐eared owl's need for habitat conservation at large spatial scales, status as a predator, and high reproductive potential that affords the species capacity to recover, make it an effective and useful candidate as an umbrella species for grassland conservation. © 2014 The Wildlife Society.

Diel activity and short‐distance movement pattern of the European spiny lobster, Palinurus elephas, acoustically tracked

AbstractThis paper presents the results of the application of an ultrasonic telemetry system to the investigation of short‐term movements in the European spiny lobster, Palinurus elephas, in a coastal area of NW Sicily (Central Mediterranean Sea). Ten lobsters were tagged with miniaturized transmitters and released over a favourable habitat and their movements then recorded by means of nine automated receivers with the objective of investigating post‐release displacement, home‐range extension, movement patterns, activity rhythm and the influence of lunar light intensity on lobster activity. Acoustic detection data were used to assess activity and home range using estimates of horizontal and vertical movements and minimum convex polygons, respectively. Continuous wavelet transform (CWT) analysis was applied to time series of position data. Acoustic data from five of 10 lobsters were successfully recorded across a 78‐day study period between April and June 2008. All of them displayed an activity pattern characterized by diurnal sheltering and nocturnal foraging, with higher activity (i.e., longer distances travelled) at night. Their home range measured between 1629 and 8641 m2, and all lobsters relocated every 4.6 days on average, probably in search of unexploited feeding grounds. For this reason we hypothesize a nomadic movement pattern for our tagged lobsters. CWT analyses highlighted a 24‐h periodicity in lobster activity, with higher activity from sunset to sunrise. No clear influence of moon phase on lobster activity was detected.