New Zealand Owlet-nightjar

The New Zealand owlet-nightjar is an extinct bird species that became extinct in the late 13th century. In Māori, it is referred to as Ruru hinapō. This species is recognized as the largest owlet-nightjar in recorded history. They ranged in weight between 150-200g. Estimates of their weight are based on allometric measurements of their bones. The New Zealand owlet-nightjar was a nocturnal bird that inhabited a range of environments across New Zealand, including dense forests, caves, and shrublands. Since this species went extinct before the widespread development of human civilization in New Zealand, no physical traits have been recorded; inferences about their appearance are derived almost exclusively from bone remains and DNA analysis. Owlet-nightjars (genus Aegotheles) are typically small to medium-sized birds characterized by broad, weak bills and an upright posture. Their weak bills are adapted for catching insects. They possess a facial disc with forward-facing eyes, which helps in sound localization and enhances hearing ability. Owlet-nightjars also do not reflect light from their eyes in the dark, which is a feature that distinguishes them from nightjars. These morphological traits found in the Aegotheles genus are consistent with those found in New Zealand owlet-nightjar remains. …

The New Zealand owlet-nightjar was distributed throughout most of New Zealand, including both the North Island and South Island. They are endemic to New Zealand and are the only known species of owlet-nightjar to have inhabited the country. They occupied a diverse range of habitats including caves, dense, wet forests as well as dry shrublands. Many of their remains, both adult and juvenile, have been discovered in caves, some much deeper than most other species, although usually at the base of cave entrances. For this reason, it is believed they likely nested in caves. Their strong legs further support this theory as they would’ve been able to climb steep rock walls of caves, despite being poor fliers. In general, almost all owlet-nightjar species (genus Aegotheles) are known to inhabit cavities and holes.

New Zealand owlet-nightjars were a nocturnal bird species, known to prefer staying hidden. They nested in caves, fissures and holes in the ground. Their main ecological roles would’ve included insect control, seed dispersal and prey for larger predators. Their main predators included laughing owls (Sceloglaux albifacie), and Pacific rats (Rattus exulans). Owlet-nightjars are not considered very social species, and often live alone or in pairs. Again, much of their exitance is not well studied, so little information on their behaviour and ecology is well known.

Diet. Based on various sources examining owlet-nightjar diets, Aegotheles species have been known to consume a variety of prey including spiders, ants, beetles, flies, cockroaches and grasshoppers. While there lacks feasible data on the diet of the New Zealand owlet-nightjar, insights can be drawn from the feeding habits of other owlet-nightjars. It is likely that the New Zealand owlet-nightjar spent most of its time on the ground, foraging for insects and other food sources on the forest floor. Hunting occurred during the night.

Nesting. There's no sufficient data on breeding habits of Aegotheles novaezealandiae. Based on the locations of their remains, it is evident that they likely nested in caves. …