Birds can sometimes have the habit of settling on the inner part of the bend of the drain/down pipe.
In these cases you have a number of options, depending on the space there is
and how tight to the facia the bend is.
The best solution by far is to use the Defender Thistle spike because (a) it
has a low profile and (b) with plastic spikes they are flexible enough to push
up tight in to the soffit/facia.