#Delphinidae

[snototter]

A pod of Hector's dolphins (Cephalorhynchus hectori) leap from the water in Aotearoa

by Anjanette Baker

[inatungulates]

Northern right whale dolphin Lissodelphis borealis

Observed by anudibranchmom, CC BY-NC

[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.

[uncharismatic-fauna]

Uncharismatic Fact of the Day

Nothing says 'bisexual' quite like bottlenose dolphins! Studies have shown that almost all males in this species are bisexual, and form close partnerships with other males at an early age. Male partners hunt together, play together, and even keep watch while the other sleeps. Couples remain together for most of their lives-- although typically both partners also freely mate with females during the breeding season.

(Image: A pair of common bottlenose dolphins (Tursiops truncatus) by Lisa Morse)

[todropscience]

DOLPHIN MOMS DO 'BABY TALK' WITH THEIR CALVES

Baby talk or Motherese/ Parentese is a speech pattern nearly universal across cultures and languages in human caregivers interacting with children. It is characterized by a higher than usual pitch, exaggerated intonation, repetition, calling attention to objects and use of slow stretchy speeches. What we know about baby talking in other nonhuman species is sparse. Now, researchers have  found evidence for baby talk in bottlenose dolphin, a species that shows parallels to humans in their long-term mother–offspring bonds and lifelong vocal learning. 

Researchers analyzed audios from made wild bottlenose dolphins in waters near Sarasota Bay, Florida, United States, and found that females produced signature whistles with significantly higher maximum frequencies and wider frequency ranges when they were recorded with their own dependent calves.

This finding provide an example of convergent evolution of motherese in nonhuman mammals, and may help us understand how motherese can facilitate vocal learning and bonding in nonhumans as well as humans.

Photo by Carli Brush Stoll

Reference: Sayigh et al., 2023.  Bottlenose dolphin mothers modify signature whistles in the presence of their own calves. PNAS

[benadrylcandlewhack]

Does anyone else find it genuinely fascinating that orcas tail-slapping their prey out of the water means that they have to have some understanding of how anything would take damage from hitting the water surface from a certain height (which is wickedly impressive for an animal that lives underwater it's whole life) or do you all just jump to calling them evil because of this

[terranlifeform]

Dusky dolphins (Lagenorhynchus obscurus) playing off the coast of Kaikoura, New Zealand

Michael S. Fuhrer (Feather as a Light)

[internetdruid]

🥚?

hourglass dolphin!

(Lagenorhynchus cruciger)

[saltycetaceans]

I'm actually alive, here's photos I've taken of Akai - who is one of the older dolphins at DCO and is going to be in his 50s very soon <3

[snototter]

A Hector's dolphin (Cephalorhynchus hectori) leaps from the water in Marlborough, Aotearoa

by Gregory "Slobirdr" Smith

[inatungulates]

Eastern Tropical Pacific killer whale Orcinus orca

Observed by azure27014, CC BY-NC

[dougdimmadodo]

Orca (Orcinus orca)

Family: Marine Dolphin Family (Delphinidae)

IUCN Conservation Status: Data Deficient 

Found in open oceans worldwide from the tropics to the poles, the Orca (also known as the Killer Whale, a mistranslation of an early Spanish name for this species, “asesina de ballenas”, meaning “whale killer”) is the largest living species of dolphin, and one of the most extensively studied of all cetaceans. Like most cetaceans Orcas live in complex social groups known as pods, but the makeup of these pods is unlike that of any other mammal in that individuals of both sexes typically remain with their mothers for their entire lives: each pod is led by a dominant female (known as a matriarch) who guides the pod in finding food, and upon her death a matriarch will be succeeded by one of her daughters. All of the males in a pod (which can be distinguished from females due to their longer dorsal fin) will be a son of one of the females within it, and while they may temporarily separate from their birth pod to mate with females from other pods they will almost always return afterwards. Different populations of Orcas differ greatly in the strategies they use to hunt and the vocalizations they use to communicate with one another, with some researchers having likened these differences to the variety of languages and cultures seen in humans. Owing to their intelligence, large size and cooperative hunting strategies, Orcas are tertiary consumers (apex predators) in every ecosystem they appear in and have been known to prey on animals as large as Blue Whales and other tertiary consumers such as Great White Sharks (although smaller prey such as sea turtles, smaller dolphins, seabirds, pinnipeds and a range of fish species are more typical prey.) 

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Animal Advent Calendar - Day 2

Image Source: https://www.inaturalist.org/taxa/41521-Orcinus-orca

[hey-its-sybarite]

Just vibin’

[hey-its-sybarite]

Rabid Seals

We didn’t know this could happen, we are worried about other marine animals. And not to be a sensationalist but someone call up Stephen King and ask him how he feels about the possibility of a rabid orca.

[terranlifeform]

Orca (Orcinus orca) off the coast of Tromsø in Norway

Bo Eide

[relatablemarine]

Terrible news everyone! Turns out the 'boymum' phenomenon is not limited to members of the human species. Female orca (Orcinus orca), especially post-menopausal individuals, often seem to spend a large amount of time coddling their useless adult sons. These mothers often share food with their larger sons and solve scuffles between them and other members of their pod. Why do these females dote on their adult sons and not their daughters? Researches believe it is all down to passing on the most of their genetic information. An orca mother only produces one calf per gestation period, a process that takes an average of 17 months and usually only has a calf every 3–5 years. A male however, can mate with multiple females per year. By ensuring their sons are well-fed and avoid fights increases their chances of procreating even more, thereby maximising the amount of individuals in the next generation carrying part of her genetic information.