#new zealand mammal

[have-you-seen-this-animal]

Southern right whale dolphins

Oh a very cool one, hadn't seen them before! Thank you!

Photos from Gerard Bodineau & Toby Dickson, respectively.

[respect-the-locals]

🐬 Daily Cetacean Fact: 🐬

Hector's Dolphin: Hector's dolphin is the only cetacean endemic to New Zealand. Similar to the Hourglass Dolphin, Hector's dolphins use high-frequency echolocation clicks. However, the Hector's dolphin produces lower source-level clicks than the hourglass due to their crowded environment. This means they can only spot prey at half the distance. The species has a very simple repertoire with few types of clicks, as well as little audible signals in addition to these.

[uncharismatic-fauna]

New Zealand Batfly (Mystacinobia zelandica)

Habitat & Distribution

Endemic to the island of Aotearoa (New Zealand)

Found in the colonies of New Zealand short-tailed bats, which reside primarily in caves, forests, and agricultural areas

Physical Description

Length: 4–9 mm (0.15-0.35 in)

Although they are true flies, the New Zealand batfly is wingless; they also lack eyes, and instead use specialized hairs to sense its surroundings

Both sexes are orange, with darker heads and lighter abdomens

Behaviour

New Zealand batflies are reliant on the guano produced by New Zealand short-tailed bats; they both feed on the guano and lay their eggs in it

They live in colonies, with males closely guarding clutches of eggs

To disperse, individuals attach themselves to the fur of the New Zealand short-tailed bat and hitch a ride to new colonies

Key Advantages

To avoid predation, males produce a high-frequency buzz that can disorient or deter bats

Due to their small size, they may difficult to find

See where they stand in the May Mammal Madness Tournament here!

Photo by Rod Morris

[sitting-on-me-bum]

Auckland Island pigs scour the coastline for food. Due to their smaller stature compared to other breeds, the pigs are better candidates for xenotransplantation.

How New Zealand’s Pesky Pigs Turned Into a Cash Cow

The animals evolved into ultra-resilient, disease-free predators while isolated on Auckland Island.

Visual: New Zealand Department of Conservation

For now, the Auckland Island pigs continue to run free, but the clock is ticking: New Zealand’s Department of Conservation has been preparing for eradication.

[valeechtine]

I'm always so happy to learn about a new critter, even if it wasn't recently discovered by any means its so fun I love when there's a new guy

[considernature]

EEEEEEEE EEEEEEEEE EEEEEEE

That's right! It's International Bat Appreciation Day! We share our planet with over 1400 species of bat, making the second most abundant mammal order, and they perform a wide variety of ecological roles, from dispersing seeds to pollinating flowers to eating thousands of insects in a single night! Over 200 bat species are listed as Threatened by the International Union for the Conservation of Nature--that is over 14 percent of all bats!

YOU can help endangered bats today by donating to Pennsylvania Bat Rescue at this link. This PA-based organization rehabilitates sick or injured bats and helps educate people like you and me in how we can create more bat-friendly environments.

If you want to learn about particularly-cool bat species native to New Zealand, check out this Consider Nature article on the Pekapeka, the bat that walks:

For the rest of the day, Consider Nature will be bat-bombing Tumblr with some of our favorite bat species to share them with the world!

Alt text: a small brown bat stretching its wings with the kind of fabulous flourish that would impress Ryan Evans.

[a-solitary-sea-rover-backup]

Today’s Ocean Race Show is short and has a tour of 1993-94 winner New Zealand Endeavour and a biologist discussing orca encounters. Well worth it!

[reasonsforhope]

"Two wild kiwi chicks were born near Wellington, New Zealand, about a year after a reintroduction program began in the city, the Capital Kiwi Project announced last week. The fluffy, brown babies are the first to be born near the country’s capital in at least 150 years. 

“This is very special for the team, which has been working hard for the last few years,” project founder Paul Ward tells the Agence France-Presse. The chicks are a “massive milestone for our goal of building a wild population of kiwi on Wellington’s back doorstep.”

These flightless, chicken-sized birds were once abundant across New Zealand, with the nation’s five species numbering an estimated 12 million individuals in total. But nonnative predators and habitat loss caused their populations to plummet. Today, approximately 68,000 kiwis remain....

Conservation and reintroduction programs, including the Capital Kiwi Project, have been working to restore a large-scale wild kiwi population for years. In 2022, the organization released 11 kiwis into the wild in Makara, a suburb about seven miles west of Wellington. Between February and May of 2023, another 52 birds were released, and 200 more are slated to be released over the next five years, reports Eva Corlett for the Guardian.

Along with reintroduction efforts, the project aimed to reduce threats from European stoats, also known as ermines. The mammals were brought to New Zealand in the 19th century in an attempt to eradicate another introduced creature: rabbits. But these weasel-like stoats are voracious predators and kill many of New Zealand’s native species, including kiwi chicks. Only about 5 percent of kiwi chicks survive to reach breeding age in areas where predators are not controlled, largely thanks to stoats. In areas under management, however, 50 to 60 percent survive. Knowing this, conservationists worked with 100 landowners across the bird’s 60,000-acre habitat to install 4,600 stoat traps.

Of the 63 adult kiwis now roaming the hilly farmlands of Makara, only about a quarter are being monitored—meaning more chicks will likely hatch in the near future. Conservationists will continue monitoring the two new chicks, though Ward tells the Guardian they still have a long way to go before they’re fully grown...

Over the years, the long-beaked birds have become a national symbol of New Zealand, with people who hail from the country often referred to as kiwis. The animals also hold special importance to the Māori people of New Zealand, who have cultural, spiritual and historic associations with the birds. Even the New Zealand dollar is sometimes referred to as the kiwi, and the bird is featured on the country’s dollar coin."

-via Smithsonian Magazine, December 6, 2023

[why-animals-do-the-thing]

Hey uh I just found this out and I'm FURIOUS but miami zoo has a kiwi bird. Which is fine if they were doing what we do here and keeping it in a darkened enclosure with clear notices to be quiet and not bang on the glass. But instead this shy, solitary nocturnal bird is being kept in broad daylight and people are being allowed to pet it. NZ twitter is out for blood right now. https://twitter.com/zoomiami/status/1637864741954637824

…fucking yikes.

The kiwi I’ve seen in other AZA zoos have been kept according to the practices you describe: dark exhibit on a flipped light cycle, in a signed quiet area. What it looks like Zoo Miami is doing is… not good.

Here’s the link to their tweet with a video about the encounter (so it’ll embed):

The video shows a kiwi out of its exhibit: on a table in what looks like a back room with bright overhead fluorescent lighting. The kiwi has no room to move around and no place to hide as people pet it and reach around it to take selfies.

What do you pay to bother the kiwi four days a week - a species which in NZ is apparently illegal to touch without permission from the Department of Conservation? $25.

Obviously it just started and I don’t know anything more about it than what’s online, but even so, this is such a bad look for an AZA zoo, holy shit. I know a bunch of new ambassador animal rules just got promulgated… I wonder if this meets them. I’ll have to go do some reading. Also, USDA is now promulgating new bird rules (it didn’t regulate birds until just recently, only mammals) so this will also have to pass their muster soon.

The guy who runs Miami’s PR, and manages the animal media like the birth of their first kiwi chick in 2019, is known for big media stunts. I’m not surprised by this but I don’t think it’s going to go over well. There’s a lot of pressure on zoos to offer new encounters and programs to help make up for inflation and pandemic losses but this not how to do it.

I’d honestly suggest New Zealanders who are upset about this contact Zoo Miami formally (more than just on twitter) using the contact form on their website, and maybe even the AZA to express concerns about this program animal’s welfare - as well as the lack of cultural awareness at one of their accredited facilities.

Edited to add: a statement from Zoo Miami is supposed to be forthcoming tomorrow. I’ll update once we have it.

[tanadrin]

Sometimes, Chris Hayes' podcast goes off on these weird tangents, and the most recent episode is one of them, quite explicitly. It's about the history of Polynesia, which is always a fascinating subject--the Polynesian expansion, and really the whole history of the Austronesian-speaking peoples, seems like one of those feats with rare equal in human history. It's one thing to roam over the vast steppes of Asia--it's quite another to take a canoe, stick some outriggers on it so it doesn't tip over, and start faring the open ocean.

One point his guest makes that I found interesting is that for the most part the atolls and little islands of the Pacific are a very harsh environment. Big volcanic archipelagoes like Hawaii and Aotearoa/New Zealand are rare. Atolls and other reef islands especially are functionally big limestone slabs, often without any source of fresh water, with no large mammals, and with few native plants you can eat. The weather is nice, sure (when there isn't a typhoon--and I can't help but think a typhoon on a little island must be terrifying indeed), but these are not inherently resource-rich places. That the Polynesian (and Micronesian and Melanesian!) peoples not only could travel those distances, but make permanent habitation on the islands they came across, is kind of crazy! You have to be really prepared, with a package of supplies and technologies that set you up for success. Long-distance trade is possible, but you're not gonna be running any kind of substantial import economy across hundreds or thousands of miles of ocean via catamarans.

The comparison that springs to mind to me isn't a historical one like the European age of exploration, which was overwhelmingly to places already peopled and productive, but to science fiction scenarios of space exploration. You'd have to have a little bit of the wild-eyed zealot to be the sort of person who ignores the cries of "there is no possible useful return on this investment" to settle most of these places. But they did! And they thrived for centuries!

[gabipaleo]

Kiwi (Apteryx) - a genus of flightless birds endemic to New Zealand. They're the smallest of the ratites, a group that includes ostriches, emus, cassowaries, the extinct moas and elephant birds - kiwi's closest relatives, with both lineages diverging 54 million years ago. There are five species of kiwi found in habitats ranging from subalpine scrub to podocarp forests throughout New Zealand. While none overlap today, they were widespread before the introduction of mammals such as stoats, the kiwi's main predator, and several species coexisted.

Despite differences in size, colour and habitat, all kiwi species share traits such as sexual dimorphism; females are larger than males, reliance on hearing and smell rather than sight, an omnivorous diet, and a nocturnal lifestyle; possibly a result of mammalian predators.

Kiwis were thought to be closely related to the extinct moa due to shared traits. However, DNA studies show they're closer to Madagascar's elephant birds, rather than to the moa, with which they shared New Zealand. The kiwi's massive eggs were once thought to be a shared trait with its relatives, the elephant birds; which laid the largest eggs ever recorded. However, it's now thought to be an adaptation for precocity, allowing the chicks to hatch mobile with yolk to sustain them. Fossils of the extinct genus of kiwi - Proapteryx, suggest that their ancestors were capable of flight and lost this ability after reaching New Zealand. This also suggests that kiwis arrived in New Zealand independently and much later than the Moas, which were already there.

[a-dinosaur-a-day]

Hi,

Apparently the winner of the 2021 New Zealand Bird of the year competition is the long tailed bat.

You read that right a BAT won a BIRD competition against 75 bird species.

Is that mammal bias enough for ya?

oh. my. gd.

[corvidaemnit]

let’s talk about the kiwi!!

(an info-dump about one of the weirdest, most scientifically interesting birds we know of today!)

so, we’ve all heard about ratites, right?

well, maybe you don’t know them by name, but you’ve most certainly either heard about them or seen them at some point.

some commonly known members of the ratite group are species like ostriches, emus, and cassowaries— as shown below:

ratites are all flightless birds within the infraclass palaeognathae— the infraclass that none other than the (now extinct) moa and elephant bird belong to!

now, these birds all share very similar characteristics; they’re large, long-necked, and long-legged with big clawed feet. all of these birds are also diurnal— which means they’re primarily active during the day time, just like us!

however, there is one species in this infraclass that is not quite like the others..

the kiwi.

not only are kiwi significantly smaller than their fellow ratites, but they also happen to be nocturnal.

and despite being small, their eggs are incredibly large, taking up to around 20% of the kiwi’s body weight, which has caused a lot of rigorous debate between scientists on exactly why.

one outdated theory suggested that perhaps the kiwi had shrunk over time from previously being very large like its ratite relatives, while its egg remained big…. but this has been debunked in recent years.

the current consensus, while still a theory, is that the egg size has to do more with precocity than anything else;

kiwis are born precocial, which makes them pretty much immediately independent upon hatching, with the ability to run and feed themselves without the help of their parents.

modern DNA analysis suggests that the size of kiwi eggs is not just a left-over trait from ‘incomplete’ evolution, but instead the exact opposite— an evolved adaptation to ensure better chances of survival.

due to their sheer size, kiwi eggs house more yolk than average, which ends up keeping newly hatched kiwis nice and fed until they learn to forage food for themselves.

when mammals began to spread in new zealand, kiwis had way more predators to worry about, and it’s theorized that they were previously unequipped to deal with this startling introduction of land-predators, such as stoats and rats, that started feeding on their eggs.

this could explain why kiwi eggs have developed to be so large over time— they give the chicks plentiful nutrients and thicker shells to ensure a better chance of survival against predation.

so… yeah. kiwis produce monster eggs and no one fully knows why just yet. neat, huh?

and that’s not even where the weirdness ends, my friends!

on top of all of this, it’s been a running joke in the bird world that kiwis are ‘honorary mammals,’ not only because of their weirdly mammalian appearance, but also because of some of their atypical biological traits.

for instance, kiwis have an average body temperature of around 38 degrees celsius .. aka, 100 degrees fahrenheit.

while this is not typical at all for birds, this is very typical for mammals, which has stumped a lot of researchers over the years.

similarly, kiwis are also the only bird in the world with exposed nostrils at the end of their beak, which can help them detect prey by using scent instead of their vision, which is very poor.

so… yeah. kiwis are the nocturnal, freakish little cousins of some of the biggest, most dangerous birds on the planet, and scientists are, quite frankly, still a little weirded out by them.

[uncharismatic-fauna]

Round One: Connoisseur Critters

Fork-marked Lemur vs New Zealand Batfly

Arena: Tropical forest

Remember, it's not a popularity contest- it's a fight to the death!

[sitting-on-me-bum]

Female sea lions on Enderby Island. The opportunistic pigs living nearby will scavenge “dead whales and seals or even krill and squid,” said Horn.

Visual: Bill Morris for Undark

[alphynix]

When owls find their way onto isolated islands lacking any terrestrial predators, they have a tendency to take up that role for themselves – evolving longer legs and shorter wings, and specializing more towards hunting on foot. From New Zealand to Hawaii to the Caribbean to the Mediterranean to Macaronesia, leggy island ground-owls have independently happened over and over again in the last few million years—

—And, unfortunately, they've all also become victims of the Holocene extinction, their fragile island ecosystems too easily disrupted by human activity and the arrival of invasive species.

The São Miguel scops owl (Otus frutuosoi) was found only in the Azores on São Miguel Island. About 18cm tall (~7"), it was slightly smaller than its relative the Eurasian scops owl, with longer legs, a wider body, and much shorter wings.

Its wing proportions indicate it would have been a poor flyer, instead primarily hunting on foot in the dense laurisilva forests. Since there were no terrestrial mammals or reptiles on São Miguel at the time, its diet probably mainly consisted of insects and other invertebrates – and it would have in turn been the potential prey of larger predatory birds like buzzards and long-eared owls.

All currently known subfossil remains of the São Miguel scops owl date only from the Holocene, between about 50 BCE and 125 CE. It's likely that it was extinct by the 1400s, following the settlement of humans in the Azores, destruction of its forest habitat, and the introduction of rodents, cats, and weasels.

———

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