This is the worst reproductive strategy in the animal kingdom

Think pandas are inept when it comes to carrying on the species? Think again. The giant panda is a champion reproducer compared to a chubby, land-bound parrot called the kakapo. Between navigational problems, botanical problems, and the occasions when horny male parrots try to have sex with animals that can kill them, this is the most hopelessly inefficient reproducer on Earth.

It's not entirely the kakapo's fault that its entire species consists of one hundred and twenty-seven animals. The eight-pound parrot had evolved in ancient New Zealand, where it kept to itself, staying away from other animals even of its own species, obsessively clipped trails to its mating habitat, and developed a bright green cloak of feathers that so perfectly matched the surrounding undergrowth that you could look right at it and not see it. The bird's stumbling block is, if you do see it, it doesn't have the instincts to do anything useful. It can freeze. It can, and more friendly species will, come right up to you. And it can, if alarmed, run up into a tree (It's an excellent climber.) and jump out to fly away. It can't fly, and so it lands in a heap on the ground, but it will attempt to fly, if stressed out. It's trying to do its part.

Sadly, nothing it tries is any use against the many mammal species - rats, possums, stoats, and cats - that have come to New Zealand along with ships, and decimated the kakapo population. Before that, the kakapo had done a pretty good job decimating themselves. It's not their fault. They live for about ninety years. They have to keep the population down some way.

This is the worst reproductive strategy in the animal kingdom

But did they have to be so good at it? In the mid-nineties, the kakapo population was down to between thirty and fifty animals in total. The kakapo has contrived, through a miracle of natural selection, to make their mating dependent on timing, acoustics, botany, and the male being able to tell a female kakapo from, say, an angry possum. None of these things should be taken for granted.

Let's start with the botanical problems. Kakapo, despite having beaks and claws that would look more appropriate incorporated into an industrial mulcher, are herbivores. They grasp branches in their claws and pull them through their beaks, stripping away the fruit and leaves. It's a hard life, and the female kakapo aren't going to make it any harder by bringing on chicks. It's only when they get a specific burst of food that the females will be interested in mating. Their favorite food, the food they eat almost exclusively when it's in season, is the fruit of the rimu tree. The rimu is a tall green tree with its fruit in the canopy, and so kakapos scale the entire thing to finally get enough food in them to make them horny. The problem is, the rimu fruits roughly every few years. And the kakapo will only mate in a high-fruit year. Occasionally there will be females fed enough to think about getting a little something every two years. More often, it's every five years. Conservation researchers, when they first found that out, felt a burst of elation. They fed up the females as much as they could, and it worked. Females mated more often and had more chicks. And the vast majority of those chicks were male. The original population of kakapo, all moved to a de-mammaled island for conservation purposes, was already mostly male. The elation turned to worry. Did the species just always tend towards male chicks? At last the conservationists noticed a trend. The heavier females produced male chicks. And since females bred during the fruiting season, they tended to be heavier when they mated. The kakapo, assisted by conservation scientists, had found yet another way to kill themselves off.

But the female species assassins were assisted, ably, by the males. It's not that the males weren't willing to mate. They were much mere consistently in the mood than the females. There were many more of them. What could be the problem?


The main one was that the kakapo is the only parrot to practice the lek system. The lek system is a practice wherein males put on competing displays for the females. Since the kakapo doesn't have the ability to fly or to fight, and is a better waddler than a walker, the only thing it has to display is its home and its voice. The male clips paths to his mating site, scoops out a nice bowl in the earth, preferably near a rock face on a cliff that will let the sound carry, and 'booms.' The booming is a deep repetitive throb with just a hint of musical overtone. It carries for miles. It sounds like it's coming from everywhere. Absolutely everywhere. Nowadays, when kakapo are concentrated in relatively large numbers on relatively small islands, it's not so much of a problem. In, for example, the majority of Fjordland, a region so mountainous and rough that sections of it are unexplored, it's a bit more frustrating to not know where whoever you want to mate with is calling from. Females were known to show up to empty mating sites and wait for days for males who were busily occupied booming somewhere else.


The males don't do themselves any favors, either. Understandably frustrated that females take the space of a college education off between breeding seasons, the males are known to breed with anything that catches their attention. This includes things like other birds, bits of the scenery, and a human's head. There are multiple video segments that show the male birds attempting to mate with the people filming them. Usually, due to the mulcher claws, the clips are accompanied by words like, "Ow! Ow! Ow!" Not all creatures, especially some of the new mammals in New Zealand, appreciate this kind of treatment. These kinds of encounters probably ended disastrously. (To be fair, this also might be why more males survived in the wild. Using the claws to try to mate with a cat is still better than just freezing up and hoping the cat loses interest.)

In the end, it looks like the kakapo's odd are actually improving. Their numbers have just about tripled, after a research program that put the females on careful diets resulted in twenty-four surviving chicks, with a majority of them being female. Slowly, they're even beginning to repopulate islands, once all the mammals and other non-native species have been cleared out. Still, the kakapo is one of the species that is now going to need constant human intervention to survive. Some researchers actually report having to help the chicks out of the eggs by using tweezers to remove the more stubborn bits of shell. Under any kind of ecological pressure, the round little ground parrot simply can't make it on its own.

Top Image: Wiki Commons

Second Image: Wiki Commons

Via ABC, Kakapo Recovery, and Last Chance to See.