Bat Call Identification

Alcathoe

This is an unusual call, but keep finding very small clusters of these calls appearing in different parts of the forest.

I've subsequently seen three whilst on an emergence survey for Pips. They look smaller than a Pip. and fly less erratically. I don't have a reliable reference source for this species, so it's here at "face value".

The second sonogram is the more typical call seen.

Barbastelle

This first sonogram is barbastelle in a high spruce canopy.

The second sonogram was taken from a Barbastelle foraging in a wide ride.

The third sonogram is of a Barbastelle emerging into the clear from a cluttered ride.

 Bechstein's Bat

 This call was recorded in Parkhurst Forest around a dense area of Ash trees. These were the loudest calls recorded and the detector was less than 6m from the bat.

Brown Long Eared Bat

This call was part of a long sequence with at least two bats visible and in close proximity. The recording was made along the Noke Common Road on the eastern edge of the Forest close to the lay-by between the Noke and Hillis Gates. The bats were flying over the uncut verge and land drain along the roadside.

Daubenton

Totally unexpected sighting, a one off three bats commuting into the forest. Maybe they've found something worth eating around the recently dug ponds? The picture is from a local house roost, again a totally unexpected visitor...

Common Pipistrelle

The level of pulse compression in all bat calls is amazing. How they deal with this information in their brain is incredible, in a modern radar or sonar you'd need several multi-core blade servers to process this data in real time...

Soprano Pipistrelle

There are small clusters of the soprano pips, all deep in old forest areas. 

Lesser Horseshoe Bat

This recording was made whilst I was recording Daubenton bats feeding over the river in Horner Woods in the Exmoor National Park. It was not until I got home and processed the night's recordings that I found I'd captured this one.

Greater Horseshoe Bat

This is also a recording from Horner Woods, this time a fly-by whilst we were watching a squadron of Noctules feeding.

Nathusius's Pipistrelle

Unconfirmed but possible Nathusius's Pip. calls;  the peak frequency is down below 40kHz, too low for common pips, and given the bat was flying towards me, probably 2 kHz higher due to doppler shift. I have number of these calls on record now, including one on emergence from a house roost, typically the call peak is down at 38 kHz.

Natterers Bat

The bat was was flying low and close pass along a grass ride. You can see the ground reflection too. I've never seen more than one natterers at a time.

Leisler's Bat

First sonogram is a Leisler's crossing almost overhead from the forest to an adjacent field.

Second sonogram is a Leisler's hawking along a ride between spruce stands.

Third sonogram is a Leislers approaching from about 50m away on improved grassland and overhead toward the forest edge. At the edge, the call became like the first sonogram.

Noctule Bat

Noctule calls are amazingly loud! They fly incredibly fast too when commuting. I didn't see the top one, but my wife following behind with the magentabat II did fortunately. It was commuting along a wide ride and heading for the farm fields to the east of the forest. There are also commuting routes to the prison farm fields, where unfortunately there is a planning application for two 125M wind turbines.

The second sonogram is the CF call out in the open.

These are both 1024 point FFTs with linear amplitude scaling.

Parti-Coloured Bat

This example was not recorded in Parkhurst Forest, but was a rescued bat being released in central Southampton.

The recording is from the bat's third and final release attempt and you can hear it flying away up to its roost six stories up in an office block...

Serotine Bat

This example is a Serotine in an edge environment. You can clearly see the noise reflected from the ground and edge, and a lower level harmonic that is divergent and crossing at 55kHz.

Whiskered Bat

This was recorded along a very wide bridle path at a junction with a wide grassed ride. Whiskered bats often appear in pairs, but not large groups like the Pips. or Barbastelles.