The woodland Constant Effort Site at Llandilo uses five nets in four rides, and being in a woodland where most of the bird activity takes place in the higher canopy, the resultant catches are fairly small, with an average of around 25 captures per five hour session. There is no influx of birds in July such as typically happens in scrub and reed bed habitats, and by late July - mid August (visits 9 to 11) the number of birds at this site is at a seasonal low, as shown in the graph below:
|The 12 annual CES sessions are spread evenly between early May and end of August|
The first half of 2018 has seen a continued drop in the number of adults following a trend since the CES began in 2015, and perhaps the arctic conditions in March affected some species, though both wren and long-tailed tit numbers seem typical, and both these species are usually sensitive to cold weather. It's too early to assess the overall number of juveniles, though the impression is that some species have done well, including long-tailed tit and robin, but others have not produced any young at all so far; blackcap and blackbird for example. The dry weather which will have reduced the number of available soil invertebrates is likely to make life difficult for any juvenile blackbirds, but its a puzzle why there are no juvenile blackcaps so far, as invertebrates seem abundant in the canopy and shrub layer. Blue tits fledged broods of up to 10, and certainly were finding it easy to find sufficient invertebrate prey.
|2018 has been the best season so far for long-tailed tit, a species which is expected to fare badly after a cold winter|