Grasshopper Warbler
An elusive species that few birders will have encountered – but how would the Grasshopper Warbler fare in a personality test?
Dominic Couzens studies the personality of this elusive species
We don’t understand Grasshopper Warblers down here in the south of England, where I live. We enjoy a small burst of birds singing on migration in the first couple of weeks of April. And then they are gone, leaving us for the grasslands, marshes and damp ditches of the west and north. Their contribution to our summer is minimal. We hardly ever hear the wonderful, reeling song, that whisper from the rank vegetation, rising and falling in strength, intermittently, as the long spring day fades into evening. We can hardly imagine that Grasshopper Warblers do what other birds do: meet up, build nests and lay eggs. These days these small, retiring birds, once relatively common at our latitudes, can seem as remote as Ptarmigans or Golden Eagles. They have done something similar to Cuckoos: retreating from the south and becoming commoner in parts of Scotland and Wales. Mind you, nobody really understands Grasshopper Warblers very well; it’s just that those in the right parts of Britain hear them enough for their presence to be instilled in the consciousness. Arguably, the Grasshopper Warbler is the most skulking small bird in the whole of Europe, in the same club as the larger Quail and Corn Crake. Except for singing males, which use moderately elevated perches (although these are usually no more than a metre or two above ground) it is almost impossible to see, let alone study. For a major British species, with some 16,000 breeding pairs in the country, it is very poorly known. Aside from the nest-finders of old, who marvelled at the sheer difficulty of finding the neat cup at the base of a grass tussock or other hiding place, few have ever had close experiences with this species.
An anonymous singer
If ever a bird fitted well into a personality type, it would be the Grasshopper Warbler and ‘Introverted.’ It doesn’t go into its shell, it stays in its shell. According to one study, males will be active and sing until about 8am, and then simply disappear until the evening. The famous ‘reeling’ song, which has been likened to the free spinning of a fishing reel or, perhaps better, to a freewheeling bicycle, tends to be heard most at dawn or dusk, but it is quite common to hear a male singing right through the night. If ever a bird wished to keep itself anonymous, what better strategy than to sing in the dark? They are also stimulated, apparently, by fog. The habit is not universal, however, and some observers have noted birds performing at all times of the day. However, if you take a look at the Grasshopper Warbler’s feeding behaviour, the same sort of introverted, skulking behaviour re-emerges. The birds habitually feed on the ground, usually in dense cover, under the shade of nettlebeds or brambles, for example. They will root around in leaf-litter like mice and, in common with the rodents, are able to walk and hop. Think how often you have seen a Grasshopper Warbler feeding – never? Think about almost every other bird – Chiffchaff, Robin, Blue Tit – you almost always see them feeding. I’ve seen Cetti’s Warbler feeding and being quite obtrusive, but not a Grasshopper Warbler.
Arguably, the Grasshopper Warbler is the most skulking small bird in the whole of Europe, in the same club as the larger Quail and Corn Crake
Think too how often you have seen a Grasshopper Warbler display – well, of course, you never have. Who ever has? And yet, during the beginning of the breeding season, these birds are perky and adventurous. Part of the pairing up process involves vigorous chases, all performed under cover of vegetation, completely hidden from us. The male (presumed) will sit on a perch and wave its wings slowly up and down, flying without taking off. There is even a ceremony when the male ruffles all its feathers, bows and carries a leaf in its bill for effect. It isn’t quite a performance on the scale of a Great Crested Grebe or a bird of paradise, but it is undoubtedly impressive for a small, retiring brown bird. Quieter people often keep their stories hidden, and so, it seems, do ‘Groppers.’ Thus, the personality of the Grasshopper Warbler is incontrovertibly confirmed as Introverted. Are there any other traits that we might establish for a fuller picture of this bird? Well, if you might forgive a somewhat eccentric indulgence, why not refer to the famous human personality test, the Myers-briggs Theory, developed by a mother and daughter team in the 1960s, adapted from the work of Carl Jung? Can we do a Myers-briggs on a bird? Why not, just for fun? In the personality tests, along with the Introvert/extravert dividing line in humans, there is also a distinction between Judging and Perception. A Perceiving personality goes with the flow, while those that tend towards Judging thrive in a world of certainties and organisation. We can confidently place the Grasshopper Warbler in the second group because, when it does most things, including foraging or building a nest, it is notably thorough and careful. Many observers have noted that, when searching on the ground, an individual will typically remain in the same place for quite some time, checking carefully for its insect food (almost all insects, only a few spiders and small molluscs.) When examining reed stems, it will quite literally search from top to bottom, searching all the leaf axils and other places where insects might be lurking. Grasshopper Warblers have even been seen foot-trembling on moist ground, presumably in an effort to flush out insects from the mud. These are the unrushed foraging methods of a bird that is at heart methodical.
Migratory behaviour
The nest is also carefully made; both sexes work in the morning to construct it, clocking off later on to feed. Throughout the nesting period the birds plod back and forth using exactly the same route, so that the nest effectively has a front drive, or a ‘run’. Perhaps this also fits in with this personality type? A further distinction in the Myers Briggs model is between Sensing and Intuition, at least in the human model. Let’s face it, a bird using intuition in most areas of its life is asking for trouble. Instead, birds are creatures of the moment, using their five senses to guide them in everything they do. Nowhere is this clearer than in their migratory behaviour (where of course they presumably use another sense, that of magnetic perception.) There is no room for wild guesses if you are trying to fly under your own steam between the Sahel region of West Africa and your breeding grounds in a Welsh bog. It is thought that the birds gather at marshes in north-west Africa before migrating here, so any deviation from the correct flight path, burnt into the DNA for millennia and followed through by watching the movements of sunset and stars, would be disastrous. The last measurement of personality in our daft analysis of Grasshopper Warblers on the couch is between Thinking and Feeling. Again, the idea of small birds thinking in an abstract way is a step too far, so once again, a Thinking personality, which veers towards being logical and consistent, fits most birds well. So, there you have it: Grasshopper Warblers are ISTJ personalities. It isn’t a bad fit, either: quiet, dependable, thorough. When they next come through my part of the world and give us a quick burst of their reeling song, I shall perhaps understand them better. Perhaps!
The nest is also carefully made; both sexes work in the morning to construct it, clocking off later on to feed