One of the challenges of behavioral research is to take notes that adequately describe the totality of what animals are doing. Since I am a behavioral ecologist, I devise a long list of behaviors that both appear important to the evolutionary fitness of loons and are also stereotyped or obvious enough for observers to record confidently on a datasheet. For example, when a loon bows its head so that its bill is pointing downwards instead of horizontally, we can all agree that it is exhibiting a “head bow”. When a territory owner slips quietly underwater, a nearby intruder flees across the water, and the owner resurfaces at the spot vacated by the panicked intruder, we recognize that the owner was “stalking” the intruder. We train field staff also to prioritize the recording of certain critical behaviors, like vocalizations, which reveal the motivational state of an animal and can be linked to particular stimuli occurring just beforehand (e.g. the flight of an intruding loon or eagle overhead). To aid new observers, we include a “cheat sheet”, shown below, that describes behaviors they are to look for and enter with our two-letter codes.
Naturally, after 27 years of loon observation, we have seen or heard most of what loons can do. Indeed, we have analyzed many of these behaviors statistically to learn why loons carry them out. Yodels are a good example. By playing yodels back from loudspeakers to flying intruders, we were able to show that this call discourages many would-be intruders from landing on a lake and confronting the territorial pair. So a territorial male can employ a yodel as a means of defending his chicks from intruder attacks. Likewise, we have inferred that the mournful wail call must play a role in keeping pairs together and advertising for mates, because loons wail with great frequency: 1) when separated from their mates, and 2) when they lack a mate altogether.
But even two and a half decades of observation and statistical analysis of behavior is not enough to prepare us for everything loons do. This fact was brought home to me a few weeks back on Swamp. Following the death of the breeding female and departure of her former mate to Burrows Lake, an interesting new breeding pair had settled on Swamp. These new breeders fit the mold of many pairs we see: the female is a former breeder on tiny Prairie Lake but was evicted from there in 2015. She is at least fifteen years old and has reared six chicks to fledging. The male is a six-year old hatched on East Horsehead with no previous breeding experience. It is probably safe to say, after watching the video below, that he is still learning. To be clear, copulation in loons, when performed correctly, requires that male and female cloacas (genital openings) make firm and stable contact for several seconds so that sperm transfer can occur.
There are a few points to make here. First, though we might expect copulation, a very simple behavior pattern, to be largely instinctive, there are evidently some motor skills related to copulation (e.g. balancing on the female’s back) that benefit from learning. So males with no previous mating experience apparently fail in some early copulation attempts and must refine the behavior. Second, complex organisms show complex, non-robotic behavior patterns, especially when interacting with others of their species. Call it vertebrate bias if you like, but grasshoppers, crabs, and earthworms show a suite of behaviors that is relatively simple to catalog and describe. Loons, like squirrels and coyotes and turtles, sometimes carry out weird actions that don’t show up in the guidebook. So loon observers need to be ready to drop the two-letter behavior codes on occasion and just write down what the birds did.
Enough about science and field techniques. What I like most about this clip is that we can relate to it. If loons were humans, you could imagine the male saying, “Ok, wait….whoops….oh no…..whoa….oh gosh….umm….ok….nobody saw that, right?”