climate

Seasonal abundance of the stable fly stomoxys calcitrans in Southwest England

The stable fly Stomoxys calcitrans (L.) is a cosmopolitan biting fly of both economic and welfare concern, primarily as a result of its painful bite, which can cause blood loss, discomfort and loss of productivity in livestock. Between June and November in 2016 and May and December in 2017, Alsynite sticky‐traps were deployed at four Donkey Sanctuary sites in southwest England, which experience recurrent seasonal biting fly problems. The aim was to evaluate the seasonal dynamics of the stable fly populations and the risk factors associated with abundance. In total, 19 835 S. calcitrans were trapped during the study period. In both years, abundance increased gradually over summer months, peaking in late August/September. There were no relationships between seasonally detrended abundance and any climatic factors. Fly abundance was significantly different between sites and population size was consistent between years at three of the four sites. The median chronological age, as determined by pteridine analysis of flies caught live when blood‐feeding, was 4.67 days (interquartile range 3.8–6.2 days) in males and 6.79 days (interquartile range 4.8–10.4 days) in females; there was no significant, consistent change in age or age structure over time, suggesting that adult flies emerge continuously over the summer, rather than in discrete age‐related cohorts. The data suggest that flies are more abundant in the vicinity of active animal facilities, although the strong behavioural association between flies and their hosts means that they are less likely to be caught on traps where host availability is high. The implications of these results for fly management are discussed.

Volume
33
Issue
4
Start page
485
End page
490
Publication date
Country

Shelter-seeking behaviour in domestic donkeys and horses in a temperate climate

Britta Osthaus
Leanne Proops
Sarah Long
Nikki Bell
Faith A. Burden
Presentation date

Donkeys and horses differ substantially in their evolutionary history, physiology, behaviour and husbandry needs. Donkeys are often kept in climates that are colder and wetter than those they are adapted to and therefore may suffer impaired welfare unless sufficient protection from the elements is provided. We compared the shelter-seeking behaviours of donkeys and horses in relation to temperature, precipitation, wind speed and insect density. Our study collected 13,612 day-time data points (location of each animal, their activity such as feeding, resting, moving, etc., and insect-related behaviours) from 75 donkeys and 65 horses (unclipped and un-rugged) with free access to man-made and natural shelters between September 2015 and December 2016 in the South-West of the UK. Each animal was observed at least once a week, with an average of 65 observations per individual overall. Even though the UK climate is quite mild (1 to 33 degrees Celsius in our sample), the preliminary results showed clear differences in the shelter seeking behaviour between donkeys and horses. Overall donkeys were observed far more often inside their shelters than horses (χ2(1)=1,783.1, P<0.001). They particularly sought shelter when it was raining: there was a 54.4%-point increase (35 to 89.4%) in the proportions of donkeys sheltering in rainy conditions, in comparison to a 14.5%-point increase in horses (9.6 to 24.1%). Results of binary logistic regressions indicated that there was a significant association between species, precipitation and shelter-seeking behaviour (χ2(3)=2,750.5, P<0.001). Horses sought shelter more frequently when it got hotter, whereas donkeys sought shelter more often in colder weather (χ2(3)=2,667.3, P<0.001). The wind speed (range 0 to 8 m/s – calm to moderate breeze) had an effect on location choice, and this again differed significantly between donkeys and horses (χ2(3)=1,946.5, P<0.001). In a moderate breeze, donkeys tended to seek shelter whereas horses moved outside. The insect-related behaviours were closely related to temperature and wind speeds. The donkeys’ shelter-seeking behaviour strongly suggests that in temperate climates they should always have access to shelters that provide sufficient protection from the environment.

Country
Published as conference proceedings
Publication date
ISBN (13-digit)
978-9-08-686322-8
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