KINGFISHERS tend to be fiercely territorial and, outside the breeding season, quite solitary. Autumn and winter can bring harsh, challenging conditions, including extreme cold, floods, and other bad weather that will disrupt fishing routines. So, each bird tries to establish its own territory, one that will sustain it through the difficult times to come.

Very occasionally (according to the literature) a territorial dispute leads to physical combat between two birds. One source suggests the chances of disputes being serious are increased if one of the protagonists is a juvenile from an early brood, that has adopted a territory since leaving its natal area, and the other is an adult that, on separating from its mate at the end of the breeding season, is returning to its winter home. In this case, the presumption is that both birds feel particularly committed to the territory, making the chances of physical aggression much greater.

I think this was the case in a dispute I recently watched. There had been at least one juvenile in the area for a little while. This can be a difficult time for juveniles, as they learn to fend for themselves. Mortality levels are high. Parents only support their offspring for approximately four days, and one account suggests that only 50% of fledglings survive their first couple of weeks. The lone juvenile that I was watching, perhaps by virtue of its abilities, or perhaps because it had happened upon a very rich territory, seemed to be doing rather well and regularly finding fish. Things were looking promising.

However, then came a day when an adult bird arrived on the scene. As outlined above, perhaps it was returning, having nested elsewhere, and this had been its territory last winter. Consistent with this hypothesis, a relatively brief period during which the two birds engaged in threat posturing did not resolve the issue of territory ownership, and soon they were engaged in a physical struggle. As tends to be the case, they locked bills and began wrestling in the water. Perhaps each was trying to exhaust its opponent. In other accounts of this phenomenon, it has been suggested that they are trying to drown one another! The struggle was brief, perhaps lasting only 15 or 20 seconds. For part of this time the birds were hidden from my view, so I was not able to see how they separated, but they were soon perched on rocks, engaging in more ‘threat posturing’. Eventually, the adult bird moved away upstream. It’s not easy being a Kingfisher!

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