Mammal Communications Papers
The diet of Eurasian otters (Lutra lutra) around the coastal fringe of Cornwall
David Groves, Rebecca J. Smith
A report outlining the findings of a citizen science project coordinated by the Cornwall Mammal Group. The project collected and analysed otter spraints from around the coastal fringe of Cornwall. Otters were found to be feeding on a broad range of prey and although a large part of the diet of otters close to the coast was marine prey, coastal spraints also included freshwater animals. Demonstrating otter dependence on coastal resources will be important in informing conservation on Cornwall’s coastal fringe.
First records of harbour seals (Phoca vitulina vitulina) breeding in SW Britain
A report of what are thought to be the first records of harbour seal births in the south west Britain region. Although found around the coast of Scotland, Northern Ireland and parts of England, harbour seals Phoca vitulina vitulina) are only occasionally seen in Wales and south west England. Two harbour pups are documented to have been born on the Dart Estuary in 2019 and a further two in 2020. It is recommended that monitoring of south west areas continue.
Annual fluctuations in harvest mouse (Micromys minutus) nest densities in southern England
Amanda Lloyd, Steven Kirk
Using aerial nest surveys, harvest mouse nests were counted over consecutive years at two sites in southern England. The study found that harvest mouse nest densities fluctuated over time. This supports the findings of other studies that indicate that populations of this rodent species undergo major fluctuations from year to year. Aerial nest surveys are the main method currently used to monitor the distribution and habitat preferences of harvest mice and the findings of this research indicate that using this method to survey for harvest mice in just one year could underestimate their likely presence at that site.
Population trends of harbour and grey seals in the Greater Thames Estuary
Thea Cox, Joanna Barker, Jon Bramley, Alison Debney, David Thompson, Anna-Christina Cucknell
Population data of harbour and grey seals in the Greater Thames Estuary are presented and the importance of long-term monitoring data to compliment seal surveys is highlighted. Results from two decades of seal population data for the area between 2003 and 2019 are shown, along with results of two harbour seal pup surveys conducted in 2011 and 2018. The most recent population estimates suggest that around 900 harbour and 3,200 grey seals reside in the Greater Thames Estuary and this area is considered an important region for both species.
Public attitudes to urban foxes in London and the south east
Adele Brand & Marc Baldwin
The study posed a questionnaire to two populations of adults and children in England in the year 2015 in order to assess ‘likeable’ and ‘reproachable’ characters of foxes. Responses were received from all 33 London boroughs and nine south-eastern counties. They found Londoners more averse to neighbourhood foxes than those in the south east and women’s attitudes were more more favourable that those of men. This data adds to information on human perception of urban wildlife and may contribute to development of conflict-resolution strategies by helping target education.
First record of True’s beaked whale, Mesoplodon mirus, in Britain
Andrew C. Kitchener, Georg Hantke, Jeremy S. Herman, Mariel ten Doeschate & Andrew C. Brownlow
This paper documents the first recorded stranding of True’s beaked whale, Mesoplodon minus, in Britain. In January 2020 a female beaked whale carcass was reported approximately 10 m above the high water mark of a bay in Scotland. A post mortem was conducted and skull examinations were used to confirm the record. The individual was 490 cm long with a maximum girth, just behind the pectoral fins, of 264 cm. This marks the fourth new cetacean species to strand in Britain since strandings schemes began in 1991. Increases in beaked whale strandings in recent years show that deep water habitats, mostly outside territorial waters, need better research and protection.
Confirmation of the presence of harbour porpoise (Phocoena phocoena) within the tidal Thames and Thames Estuary
Anna-Christina Cucknell, Anna Moscrop, Oliver Boisseau & Richard McLanaghan
This study used strandings, dedicated surveys and opportunistic sightings to document the presence of harbour porpoises in the tidal Thames. A visual and acoustic vessel survey was undertaken, documenting 17 sightings and 45 acoustic detections of porpoise groups, and an estimated 4.2 animals per 100 km – comparable to other surveys in important European habitats. Opportunistic sightings report porpoises in the area during all months with peak presence in spring and late summer. Results support the consideration of harbour porpoises when planning future activities and development within the estuary.
Measuring the effect of wing tears on flight in common pipistrelle bats (Pipistrellus pipistrellus)
Rana Osama S. Khayat, Kirsty J. Shaw, Charlotte Mead, Hazel Ryan, Gary Dougill, Louise M. Melling & Robyn A. Grant
This study used a new method to measure the effect of bat wing tears on common pipistrelle bats. The bats were filmed and the footage was used to track wing movements and body positions using software. Bats with bilateral tears moved their wings using smaller movements and more wing beats per second. Bats with tears also tended to tilt their body towards the healthier wing. Results suggested bat flight may be affected by wing tears and that further work should investigate whether this affects ability to forage and survive.
Displacing and translocating hazel dormice (Muscardinus avellanarius) as road development mitigation measures.
Nick C. Downs, Mike Dean, David Wells & Alisha Wouters
Hazel dormice occupying a dense road verge landscape in Wales were translocated due to the construction of a new road junction and slip roads on a dual carriageway. The dormice were monitored prior to construction before being displaced into retained habitat in parallel with translocation. Of the 29 dormice captured, 90% were successfully released. Prior to release, dormice were retained in soft-release cages. Their preference for blackberries, fresh hazel and nuts at this time prompted early Autumn as the recommended season for translocation of this species.
Are badgers Meles meles effective dispersal agents for bramble Rubus fruticosus agg. in Ireland?
Mary O’Sullivan, Peter W. Jones & D. Paddy Sleeman
Four aspects of the dispersal of bramble by badgers were studied: plant distribution, occurrence of fruits in diet, damage to seed during ingestion and effects on seed germination. Bramble plants were concentrated around a main sett and associated latrines Plants represented the main food items, with bramble seeds being by far the most common seeds present. Seeds revealed little damage after passage through the gut of badgers. Egested seeds germinated than seeds in intact fruits. This suggests that badgers are effective dispersers of brambles in Ireland.
A pilot study of a novel method to monitor weasels (Mustela nivalis) and stoats (M. erminea) in Britain.
Elizabeth Croose & Stephen P. Carter
A pilot study was undertaken to determine the efficacy of a novel method for detecting the presence of live weasels and stoats. The ‘Mostela’, a wooden box containing a plastic tunnel and a camera trap, was used at three sites in England. Weasels were detected at all three sites, the time to an initial detection at a site ranged from 16 to 54 days. Stoats were detected at one site. A high number of trap nights was required to achieve a relatively low number of detections. The method shows potential for future surveys and research, particularly on weasels.
An improved identification marking method for hedgehogs.
Nigel Reeve, Clare Bowen and John Gurnell
An improved identification marking method for hedgehogs has been devised using 10 mm lengths of yellow plastic sleeving bearing pre-printed animal identification numbers. Hedgehogs were marked with duplicate numbers in a single central patch just behind the crown of the head; easily visible in both active and rolled-up hedgehogs. The tags have minimal welfare implications, do not interfere with the function of the spines and can be easily read by anyone finding the animal. This method is very effective, requires minimal handling and is suitable for use by volunteer field workers.
Surveying small mammals in urban hedges
Eleanor Atkins, Ruth Swetnam, Paul Mitchell and John Dover
The suitability of hedges and non-hedge linear boundaries for small mammals in urban Stoke-on-Trent were assessed in 2015 and 2016 using baited hair tubes and footprint tubes. Small mammals were found in 63% of all study hedges and 10% of non-hedge linear boundaries, with the upper levels of hedges used as frequently as the base. Hawthorn and privet hedges showed significantly more signs of small mammals than beech hedges or non-hedge linear boundaries. The findings suggest that we should protect and enhance our urban hedgerow resource as a valuable habitat for urban small mammals.
Joshua Twining, Johnny Birks, John Martin and David Tosh
Artificial den boxes have been used to supplement denning sites of the European pine marten (Martes martes) in Scotland and Northern Ireland where natural arboreal cavities are scarce. Here, information on food caches from annual checks are reported. Pine martens predominantly cached birds, largely juvenile passerines, followed by small mammals and amphibians. This investigation highlights the potential importance of food caching in the species, as well as the ability of artificial den box schemes to explore enigmatic aspects of marten ecology in the future.
Murray Bracewell and Nick C. Downs
Non-hibernating hazel dormice (Muscardinus avellanarius) construct nests in shrub and tree vegetation up to 10 m above the ground. They also readily use and build nests in boxes, which are often used as a tool to monitor populations. The availability of natural nest materials may affect nest site selection or nest box utilisation and to gain a better understanding of this we analysed the materials used in 56 dormouse nests, collected from boxes within six southern English woodlands in 2009, and estimated collection distances. The contribution individual nest materials made to the nests were assessed using dry weights.
An estimate of the annual number of hedgehog (Erinaceus europaeus) road casualties in Great Britain
David E. Wembridge, Martin R. Newman, Paul W. Bright and Pat A. Morris
Counts of hedgehog (Erinaceus europaeus) road casualties identified in car surveys have been used previously only once to estimate road traffic mortality nationally (Morris, 2006). Here, data from four surveys (conducted between 1952 and 2004) were used to estimate annual road-casualty numbers in Great Britain. The estimate of 167,000–335,000 is substantially greater than Morris’ (2006) value, with possible implications for hedgehog conservation.
Margaret M. Andrews and Peter T. Andrews
Paul Chanin, Catherine O’Reilly, Peter Turner , Lisa Kerslake, Johnny Birks & the late Michael Woods
Summary The use of ‘DNA barcoding’ using mitochondrial DNA to study the diet of dormice was investigated. Half of the 26 samples contained insect DNA, from four species of Lepidoptera and one Dipteran. It was concluded that this is a practical approach to investigating dormouse predation on insects and discuss its limitations.
Mammal Notes 2009 – 2012
Mammal Communications were initially launched in 2009 under the name Mammal Notes. Here are Notes submitted between 2009 and 2012:
In the UK, road casualties are considered to be a significant mortality factor for badgers. Ireland is unusual in having a very high number of small rural roads with low traffic densities and low speeds. Intensive studies in such areas where the population of badgers was known showed that the mortality rate was much lower than in the UK, approximating to 1%.
D. Paddy Sleeman1 , Daniel M. Collins2 & John Davenport1, 2012. What proportion of badgers (Meles meles) are killed on roads in rural areas in the Republic of Ireland? , p.4.
Because badgers spend time underground and forage in forested areas where unobstructed views of satellites are not possible, two approaches to obtaining location fixes from GPS collars were tested. Success in obtaining fixes was significantly higher with sampling intervals of 5 minutes (79%) than with sampling intervals of 60 minutes (50%).
Brendel, C. et al., 2012. Testing a Global Positioning System on free-ranging badgers Meles meles. , p.5.
Data from a four-year study of common dormice were analysed to see if they preferred nest boxes or nest tubes. Boxes were spaced at 30m, with two tubes between each, 10m apart, along a road and on the central reservation (100 boxes, 200 tubes). Sixty two dormice were marked and captured a total of 110 times. Thirteen of the captures were in tubes indicating that where a choice is available, boxes are preferred.
Chanin, P. & Gubert, L., 2011. Surveying hazel dormice (Muscardinus avellanarius) with tubes and boxes: a comparison. , 4, p.6.
Records of stoats and weasels are shown to be rare in archaeological faunas in Britain and their absence from Mesolithic records may be a consequence of this. The co-occurrence of lemmings and stoats at some sites suggests an early arrival and native status for the species rather than introduction by humans.
Yalden, D.W., 2010. The history of stoats Mustela erminea and weasels M. nivalis in the Post-glacial of the British Isles. , p.4.
A standardised method for monitoring hedgehogs was tested at 30 sites in the UK. Surveyors carried out transects using hand held torches. 97 surveys were carried out and hedgehogs detected on 14. The low level of encounters was believed to reflect local populations. Increasing transect length would increase encounters but the method may be unsuitable for quantitative assessment.
Poulton, S.M.C. & Reeve, N.J., 2010. A pilot study of a method to monitor hedgehogs (Erinaceus europaeus). , p.4.
Badgers were observed to eat the fruits of yew trees in Kew Gardens, London. The leaves and seeds of yew contain toxic alkaloids. Seeds in badger faeces were tested for the presence of these which were found at similar concentrations to those of uneaten seeds. It was concluded that badgers can safely eat yew ’berries’ because the toxic seeds are not digested.
Gasson, P.G., Lees, J. & Kite, G., 2009. How do badgers eat yew “berries” without being poisoned? . , p.2.