Previously we’ve dedicated blogs to discussing the uniqueness of our native species to show why our conservation work is so critical. Today, we’re taking it a step further and delving into 7 weird and wonderful reproductive habits of NZ native species. (The non-human ones. That should go without saying).
By the Department of Conservation
Whether you’re looking to celebrate Valentine’s Day with some niche native species knowledge — there are other ways, but each to their own — or maybe looking to ignore the whole thing …
Here’s the blog you didn’t know you were looking for.
This is how some of our native species get down.
1) Dactylanthus depend on bats
This one’s a story of the birds and the bees – and the bats.
The dactylanthus, or pua o Te Rēinga (“flower of the underworld”), is the only native fully parasitic flowering plant and has no roots, drawing all its nutrients from its host plant.
Unlike many flowers, this one exudes a strong, musky perfume with hints of mammalian sweat – a cunning plan to get the pekapeka/short tailed bats to play Cupid.
The small native bats are attracted to the scent and the sweet nectar (up to 1ml in each flower) and so they carry pollen from plant to plant.
Sadly, with so few pekapeka around, there are less opportunities for dactylanthus to send love letters to each other.
Other introduced browsers are also attracted to the nectar and some, like possums, destroy the flowers in the process of getting nectar, which is one of the major reasons the species is in serious decline.
2) Hihi mate face to face
If you avidly followed the 2020 Bird of the Year shenanigans, which saw kākāpō crowned (that’s wonderful, we love our potpourri-smelling pals, but every bird deserves the win); then you might already know some of the following, due to a rather special campaign endorsement which we probably shouldn’t link to from here. You have Google for that.
Hihi have complex reproductive proclivities. Male birds pair up with a female in their territory while also seeking to mate with other females in the neighbourhood. To ensure the chicks are his, males need to produce large amounts of sperm to dilute that of other males — which results in larger than usual testicles. Hihi are also the only birds to mate face to face.
Most importantly, hihi are classed as Threatened–Nationally Vulnerable. In pre-European times, hihi were found throughout the North Island and on several islands, but sadly the species became extinct on the mainland with the last recorded sighting in the Tararua Ranges in 1883.
Habitat loss, the introduction of mammalian predators such as cats and rats and specimen collection contributed to the decline of hihi on the mainland. They also appear to be especially prone to the effects of disease, likely via introduced domestic birds.
3) Conifers are named for their reproduction habits
(A naming practice we can all be grateful is not allowed among the human population).
Conifer is latin for ‘cone-bearing,’ referring to the structure that lets some of Aotearoa’s classic trees – like rimu, tōtara, and miro – make baby trees.
There are two types of cones: the pollen cone, and the seed cone, which develops into the seed after fertilisation. While some species have either pollen or seed cones on one plant, others have both on an individual tree and see no need to look further afield for love.
A fertilised seed cone develops into a surprisingly weird and beautiful structure, often with a bright fleshy receptacle to hold the seed.
The fruits of this romance take time. It’s six months to three years just for the seeds to mature, let alone the time for a tree to grow.
4) Toroa/Northern Royal Albatross shake their goods to try and attract a mate
Most of us like a little privacy when we’re trying to woo a mate, unless we’re the go-to-an-island-and-stream-it-on-free-to-air-tv type; but for the Toroa/Northern Royal Albatross colony at Tairoa Head, that’s not an option.
This colony are streamed 24/7, and have been since 2016 when we set the camera up. The goal was to create a conservation communication initiative which would connect viewers directly with nature, so they could see with their own eyes how the breeding season works, and some of the challenges of conservation, including plastic pollution and climate change.
Currently, the camera on the peninsula is run in partnership with Cornell Lab of Ornithology.
Setting up a camera and knowing it’ll capture breeding season is one thing, but seeing it is entirely another.
After a successful fledging, the parents leave the colony for a year at sea before returning to breed again, completing a two-year cycle. If the pair fails to breed they may return in consecutive years until they are successful.
Adolescents return to look for a mate at 3–8 years of age. They gather on ridgelines where the male birds display their virility by stretching their wings, throwing their heads up and screaming raucously, while admiring females gather round and take part in elaborate courtship rituals.
We’re not saying this is similar to Saturday nights at bars, but we’re not not saying that either.
5) Archey’s frog dads don’t shirk parental duty
The dating life of the tiniest frog in Aotearoa remains somewhat of a mystery, but we know they don’t do it the cliché frog way. (If you listen closely, you may be able to hear our Herpetologists cringing at the anthropomorphising we’re running away with here).
The Archey’s frog lives in cool damp bush areas, away from water. They’re silent and have no mating call. Rather than climbing on top of the female like other frogs, the male will hold the female in a close lover’s embrace around the waist – although we still don’t know exactly how they consummate their passion.
They continue to break with what we may think of as frog tradition in family life too. When the eggs are laid, the female heads off and leaves the male to protect the eggs – and rather than hatching into tadpoles, they develop into froglets. These froglets climb onto Dad’s back and hang out there until they finish developing into frogs.
6) Trapdoor spiders without rhythm get eaten
Trapdoor spiders live in burrows that (have you guessed?) have a trapdoor at the end. The female is so confident in the home they’ve made they’ll never leave it, not once in the potential 25 years of their life.
It’s up to the male to venture from their tunnel home and seduce a prospective partner by drumming on the trapdoor with their front legs.
Evidence suggests a budding musician who doesn’t play a beat the female likes may be eaten.
Perhaps there’s a good dating tip here – don’t rock out your guilty music pleasures on a first date.
7) Stick insects struggle when looking for love/friendship
The thing about stick insects is they look like sticks. You might assume the critters themselves have some kind of innate ability to spot friends from foliage, but it seems that they’re as unsure as the rest of us.
(This is an exaggeration, but only slightly).
Since it’s hard to visually identify other stick insects in the forest canopy, stick insects rely on smell to distinguish between peer and twig.
So like many insects, our sticky pals release pheromones recognised only by other members of their species.
Even so, it boggles the mind to think of a stick instinct sidling up to a promising looking, luscious protrusion of a possible mate; only to discover that the object of their affection was, in fact, just a stick.
Another fun fact: many species of stick insect are parthenogenic; which means females can lay fertile eggs without mating with a male.