Cormorant

I've been seeing a lot more of these birds along the canal in the last couple of years. They are large, dark waterbirds with just 2 species found in the UK, one essentially marine & the other found on all kinds of waters. Having spent some time trying to photograph them, I noticed they swim very long distances under water. Trying to predict where they might surface again is totally unpredictable in terms of directions as well as distance!