August 18 2016

Notes

The Barbastelle model shows very strong preferences for older deciduous woodland areas. Barbastelles have been found to be widespread across the Island, but the peak areas of activity are Parkhurst Forest and Brighstone Forest.

The Serotine bat is widespread through the Island, however there are some noticeable peaks in the model and survey data.

The Bechstein's bat is extremely difficult to detect, and most of the data driving this model has come from the Isle of Wight Woodland Bat Survey conducted by Ian Davidson-Watts. We have have found Bechsteins close to Bloodstone Copse, Borthwood Copse and Parkhurst Forest using static acoustic detection.

The model shows a strong link to deciduous woodland, however the areas we have detected Bechsteins are all rich with older Ash trees.

Not surprisingly, most of the Daubenton bat detections have been close to water, and the model is showing the peaks where there is both water and woodland.

The Whiskered bat is common across all the deciduous woodland areas we have surveyed and this has shown up the model too.

Although widespread, we have not encountered large numbers of Natterers bats in the surveys this year. The model shows links with urban areas, which has been driven by the relatively high percentage of bat rescue presences in the data.

The Noctule can be found almost anywhere on the Island where there is food to be had. They are very common over large water areas, bit will also be found foraging in open fields, or commuting to/from their roosts.

The Nathusias' Pipistelle is a common visitor to the Island, and it often shows up in our recordings. The call is distinctive from the Common Pipistrelle because it peaks at around 38kHz. We've only ever recorded the species on relatively low lying ground, hence the large areas of blue that correspond to higher ground.

The Common Pipistrelle is totally pervasive through the Island, but there are definite areas of peak activity that have been found the match the current model predictions.

Most of the Soprano Pipistrelle sightings have been in the North and East of the Island, and they have never shown up on high ground, hence the habitat bias preference to the lowland areas shown in this baseline.

Brown Long-Eared bats are extremely difficult to detect by acoustic survey, and like the Bechstein, we have tended to pick these up from long term static surveys only. So the bulk of the data is from bat rescues and the Isle of Wight Woodland Bat Survey data. There are strong links to urban areas driven by the rescue data and sheltered woodland areas.

We've not recorded any Grey Long-Eared bats this year, and the model is informed by previous bat rescue and other local record centre data. You also need extremely clear recordings in order to be able to reliably separate the Brown and Grey Long-Eared Species...

We've not recorded any Greater Horseshoe bats so far this year, so the model has been informed by the LRC data which includes bat rescues, hibernation roost surveys, and one acoustic recording made in Parkhurst Forest last year. They have only been found where you have roost potential, organic cattle and woodland edges onto the grazing areas. There are not really enough data points in this model to be really sure what it is telling us as it is peaking in the high hibernation roost potential areas, which is the main component of the presence data.