Chapter 23: An obsessive Hobby

The last two don’t sound much like the others, but show that there is even potential for confusion between Hobby and Peregrine. I actually recorded that pair of Peregrines interacting at dusk one winter on Soldier’s Road, where you can see Hobbies a few months later. 

Maybe I just don’t hear enough of the real thing, and yet with about half a dozen pairs of Hobby in the harbour I get to see them often enough. The adults arrive in May, while some yearlings pop back in June for a bit of prospecting. Other young Hobbies stay on their wintering grounds, or else move north but not far enough to reach Poole Harbour.

So how can we tell Hobbies apart from some of the species that give similar sounds? Wryneck can sound very similar indeed, and although they are rare in the harbour, the potential for confusion does exist. Magnus tells me that the more Wryneck-like examples of Hobby in our collection all start with an acceleration, coinciding with a slight rise in pitch. In other words, at the start of a call the notes become progressively shorter and higher-pitched before stabilising. You can hear this clearly in CD2-82, a male and female calling in turn having recently returned to their breeding grounds. In Wryneck, there is a slight rise in pitch too, but none of our recordings show an obvious acceleration. If anything there is sometimes a slight deceleration, the first note or two being noticeably shorter, as if the bird stutters to get started. You can hear this from a male and female calling in alternation in CD2-83.

Of the other species you listened to, Kestrel is a common relative of Hobby, allowing plenty of opportunities both for mistakes and learning. Some of the faster call types of Hobby are similar in pitch and repetition rate to Kestrel calls, and one way to tell them apart is to listen carefully to the individual notes. In Hobby, each note in the faster call type descends sharply in pitch (CD2‑84). This is not the case with Kestrels, where if anything, each very short note sounds as if it rises rapidly (CD2-85). In fact the pitch then goes down again, but this is hardly audible. As the example shows, Kestrels also tend to have a slightly harsher timbre.

Hobbies also have a very short kip call that is shared by several other falcon species. In CD2-86 it is given by an adult, as a response to several other Hobbies flying over its territory. Very young Hobbies still on the nest can be identified by the weaker, scratchier quality of their calls (CD2-87). The sound we hear most often from Hobbies is a far-carrying, insistent pee-pee-pee, as in CD2-88, although we don’t usually hear it with White-tailed Eagles in the background. I should explain that it was Dick Forsman who made the last two recordings, near his holiday home in the southwest corner of Finland. I wouldn’t mind hearing either of these raptors more often in Poole Harbour. 

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