Hannah Owens
@hannahoish.bsky.social
She/her. Fixed-term Assistant Professor; Center for Macroecology, Evolution, and Climate and Center for Global Mountain Biodiversity; Globe Institute; Copenhagen University. Ecology & evolution w/ natural history collections and R. #FishADay Ally is a verb
#FishADay Champsocephalus gunnari Mackerel Icefish. Southern and Southern Atlantic oceans. In family of fish whose blood lacks hemoglobin, hence common name, White-Blooded Fish, and one of few Southern Ocean fishery species, off Heard and MacDonald islands.
fishesofaustralia.net.au/home/species...
fishesofaustralia.net.au/home/species...
Champsocephalus gunnari
Mackeral Icefish
fishesofaustralia.net.au
November 21, 2025 at 3:14 PM
#FishADay Champsocephalus gunnari Mackerel Icefish. Southern and Southern Atlantic oceans. In family of fish whose blood lacks hemoglobin, hence common name, White-Blooded Fish, and one of few Southern Ocean fishery species, off Heard and MacDonald islands.
fishesofaustralia.net.au/home/species...
fishesofaustralia.net.au/home/species...
#FishADay Sphyrna media Scoophead. Tropical Atlantic and East Pacific over continental shelf. Formerly abundant, now critically endangered, likely due to intense fishing pressure. Most recent record WAS in 2010, but one was just caught last year off Guatemala.
www.sciencedirect.com/science/arti...
www.sciencedirect.com/science/arti...
Redirecting
doi.org
November 20, 2025 at 9:02 AM
#FishADay Sphyrna media Scoophead. Tropical Atlantic and East Pacific over continental shelf. Formerly abundant, now critically endangered, likely due to intense fishing pressure. Most recent record WAS in 2010, but one was just caught last year off Guatemala.
www.sciencedirect.com/science/arti...
www.sciencedirect.com/science/arti...
Oh boy. hadley.github.io/genzplyr/
dplyr but make it bussin fr fr no cap
`genzplyr` is an alternative syntax for `dplyr` that replaces boring old function names with GenZ slang. Your data wrangling is about to hit different.
hadley.github.io
November 18, 2025 at 5:29 PM
Oh boy. hadley.github.io/genzplyr/
Anyone in this space apply for and/or receive an ERC Consolidator or know someone who has? Or has served on a panel? I think I have a great idea, but I'm trying to figure out the landscape. #ERC #ERCCoG
a cartoon of spongebob holding a pencil and writing on a piece of paper
ALT: a cartoon of spongebob holding a pencil and writing on a piece of paper
media.tenor.com
November 6, 2025 at 2:02 PM
Last major paper of my #MSCA is finally out!! I modeled and mapped over 300 fish species in three orders in 3D to demonstrate how incorporating a depth perspective may offer a view of open-ocean biodiversity patterns that differs from a typical 2D approach.
onlinelibrary.wiley.com/doi/10.1111/...
onlinelibrary.wiley.com/doi/10.1111/...
Depth Matters for Marine Biodiversity
Aim Studies on the geographical distributions of marine species have typically ignored the oceans' inherent 3D nature, instead focusing on two-dimensional patterns based on surface or near-surface a...
onlinelibrary.wiley.com
November 6, 2025 at 9:57 AM
Last major paper of my #MSCA is finally out!! I modeled and mapped over 300 fish species in three orders in 3D to demonstrate how incorporating a depth perspective may offer a view of open-ocean biodiversity patterns that differs from a typical 2D approach.
onlinelibrary.wiley.com/doi/10.1111/...
onlinelibrary.wiley.com/doi/10.1111/...
Reposted by Hannah Owens
Happy #Halloween 🎃Since this fellow was so popular we are once again sharing spooktacular illustrations of Vampyroteuthis. The 'vampire squid from hell' is neither squid nor vampire, using sticky filaments to feed on marine snow
📖 Reports from the German Deep-Sea Expedition 'Valdivia' 1898-1899
📖 Reports from the German Deep-Sea Expedition 'Valdivia' 1898-1899
October 31, 2025 at 10:00 AM
Happy #Halloween 🎃Since this fellow was so popular we are once again sharing spooktacular illustrations of Vampyroteuthis. The 'vampire squid from hell' is neither squid nor vampire, using sticky filaments to feed on marine snow
📖 Reports from the German Deep-Sea Expedition 'Valdivia' 1898-1899
📖 Reports from the German Deep-Sea Expedition 'Valdivia' 1898-1899
#FishADay Varicus lacerta Godzilla Goby. Known from mesophotic reef off Curaçao, only known from one specimen. Recent explorations of deep reefs worldwide by submersibles and technical divers have shown there is still LOTS of work for marine fish taxonomists to do.
blog.pensoft.net/2016/06/08/t...
blog.pensoft.net/2016/06/08/t...
The Godzilla goby is the latest new species discovered by the Smithsonian DROP project | Blog
As part of the Deep Reef Observation Project (DROP), initiated by the Smithsonian Institution, a new goby fish species was discovered in the southern Caribbean. Living at depths greater than conventio...
blog.pensoft.net
October 31, 2025 at 10:02 AM
#FishADay Varicus lacerta Godzilla Goby. Known from mesophotic reef off Curaçao, only known from one specimen. Recent explorations of deep reefs worldwide by submersibles and technical divers have shown there is still LOTS of work for marine fish taxonomists to do.
blog.pensoft.net/2016/06/08/t...
blog.pensoft.net/2016/06/08/t...
Very happy to see another paper out in which I had a small part to play. Big congrats to Erika Páez V., et al.!
doi.org/10.1111/syen...
doi.org/10.1111/syen...
Phylogeny, systematics and evolution of mimicry patterns in Neotropical limenitidine butterflies
The most comprehensive phylogeny for Adelpha reveals that it is not monophyletic, supporting the description of the new genus Adelphina for the alala-group. The rate of mimicry evolution increases t...
doi.org
October 31, 2025 at 9:32 AM
Very happy to see another paper out in which I had a small part to play. Big congrats to Erika Páez V., et al.!
doi.org/10.1111/syen...
doi.org/10.1111/syen...
#FishADay Parupeneus cyclostomus Yellow-saddle Goatfish. Indo-Pacific Reefs. Chemosensory barbels snuffle through substrate to detect prey, but have also been observed hunting cooperatively with other goatfish or even octopuses, such as this Day Octopus.
www.youtube.com/watch?v=IpQ_...
www.youtube.com/watch?v=IpQ_...
UNLIKELY FRIENDS: THE OCTOPUS AND THE GOATFISH
YouTube video by Trond Amundsen
www.youtube.com
October 27, 2025 at 2:29 PM
#FishADay Parupeneus cyclostomus Yellow-saddle Goatfish. Indo-Pacific Reefs. Chemosensory barbels snuffle through substrate to detect prey, but have also been observed hunting cooperatively with other goatfish or even octopuses, such as this Day Octopus.
www.youtube.com/watch?v=IpQ_...
www.youtube.com/watch?v=IpQ_...
Reposted by Hannah Owens
I'm hiring!⭐ As part of the DFF Sapere Aude-funded project MiddleEarth, I am looking for 1 postdoctoral researcher and 1 research assistant.
October 27, 2025 at 9:54 AM
I'm hiring!⭐ As part of the DFF Sapere Aude-funded project MiddleEarth, I am looking for 1 postdoctoral researcher and 1 research assistant.
Got up super early on Saturday to virtually attend a #CIAC2025 workshop in Okinawa as an invited speaker on 3D species distribution modeling. Looking forward to seeing these tools used to help recognize cryptic cephalopod biodiversity!! #voluModel
October 26, 2025 at 10:15 AM
Got up super early on Saturday to virtually attend a #CIAC2025 workshop in Okinawa as an invited speaker on 3D species distribution modeling. Looking forward to seeing these tools used to help recognize cryptic cephalopod biodiversity!! #voluModel
#FishADay Opasanus phoebotron Scarecrow Toadfish. Near-shore Caribbean, but seemingly absent from Florida, 7-16 cm total length. While there is not a lot out there about the species, the original description from 1961 makes for a fun read (see below).
digitallibrary.amnh.org/server/api/c...
digitallibrary.amnh.org/server/api/c...
October 23, 2025 at 11:16 AM
#FishADay Opasanus phoebotron Scarecrow Toadfish. Near-shore Caribbean, but seemingly absent from Florida, 7-16 cm total length. While there is not a lot out there about the species, the original description from 1961 makes for a fun read (see below).
digitallibrary.amnh.org/server/api/c...
digitallibrary.amnh.org/server/api/c...
#FishADay Hypophthalmichthys molitrix Silver Carp. Threatened in natural habitat (rivers of continental eastern Asia); widely aquacultured and introduced for food production and water quality control. Breed quickly, grow large, and in some places jump when startled.
youtu.be/LEAc1C48Yo4
youtu.be/LEAc1C48Yo4
Invasive Species - Silver Carp
YouTube video by MOconservation
youtu.be
October 22, 2025 at 1:08 PM
#FishADay Hypophthalmichthys molitrix Silver Carp. Threatened in natural habitat (rivers of continental eastern Asia); widely aquacultured and introduced for food production and water quality control. Breed quickly, grow large, and in some places jump when startled.
youtu.be/LEAc1C48Yo4
youtu.be/LEAc1C48Yo4
#FishADay Coryphaenoides armatus Abyssal Grenadier. Abyssal and cosmopolitan, generally between 800 and 5,493 m. Evidence from brain development suggests juveniles hunt by sight, adults by smell.
Enjoy this supercut of C. armatus and friends, care of @mbarinews.bsky.social
youtu.be/O7CXprStVdo?...
Enjoy this supercut of C. armatus and friends, care of @mbarinews.bsky.social
youtu.be/O7CXprStVdo?...
Take a meditative moment and gaze into the eyes of the deep-sea rattail fish
YouTube video by MBARI (Monterey Bay Aquarium Research Institute)
youtu.be
October 21, 2025 at 9:49 AM
#FishADay Coryphaenoides armatus Abyssal Grenadier. Abyssal and cosmopolitan, generally between 800 and 5,493 m. Evidence from brain development suggests juveniles hunt by sight, adults by smell.
Enjoy this supercut of C. armatus and friends, care of @mbarinews.bsky.social
youtu.be/O7CXprStVdo?...
Enjoy this supercut of C. armatus and friends, care of @mbarinews.bsky.social
youtu.be/O7CXprStVdo?...
Reposted by Hannah Owens
Please pass along, I’m recruiting PhD students to join our Macroecology Lab @uofa-eeb.bsky.social We study phys ecology, macroecology, biodiversity - spanning scaling, trait-based ecology, theory, comparative biology & ecoinformatics. Several avenues for funding. Please reach out if interested🧪🌐🌾
October 21, 2025 at 5:13 AM
Please pass along, I’m recruiting PhD students to join our Macroecology Lab @uofa-eeb.bsky.social We study phys ecology, macroecology, biodiversity - spanning scaling, trait-based ecology, theory, comparative biology & ecoinformatics. Several avenues for funding. Please reach out if interested🧪🌐🌾
#FishADay Isurus paucus Longfin Mako Shark. Cosmopolitan in tropical and temperate pelagic waters, but distribution not well documented. Reproduce via aplacental viviparity--hatch inside uterus, young continue to develop prior to birth, sustained by nonviable eggs. www.youtube.com/watch?v=bXs2...
Marrajo negro (Isurus paucus)
YouTube video by Tiburones en Galicia
www.youtube.com
October 20, 2025 at 11:51 AM
#FishADay Isurus paucus Longfin Mako Shark. Cosmopolitan in tropical and temperate pelagic waters, but distribution not well documented. Reproduce via aplacental viviparity--hatch inside uterus, young continue to develop prior to birth, sustained by nonviable eggs. www.youtube.com/watch?v=bXs2...
#FishADay Prionotus miles Galapagos Sea Robin. Sand rubble bottoms off rocky reefs in the Galapagos Islands. As with other sea robins, first three pectoral fin rays highly modified into little spider legs it uses to creep along the seafloor, probing for goodies. youtu.be/h_UVOW5pcAw?...
GALAXY27NOV20414
YouTube video by Roberto Peralvo
youtu.be
October 17, 2025 at 3:01 PM
#FishADay Prionotus miles Galapagos Sea Robin. Sand rubble bottoms off rocky reefs in the Galapagos Islands. As with other sea robins, first three pectoral fin rays highly modified into little spider legs it uses to creep along the seafloor, probing for goodies. youtu.be/h_UVOW5pcAw?...
#FishADay Liparis mucosus Slimy Snailfish. NW Pacific coast. Up to 13cm, color varies from brown to red. Not to be confused w/ widespread orchid genus of same name, from Liparos, "oily" or "shiny"--leaves in orchid's case, whole critter in snailfish's case. www.inaturalist.org/taxa/223898-...
Slimy Snailfish (Liparis mucosus)
Liparis mucosus, or the slimy snailfish, is a fish from the genus Liparis. The fish can be found from intertidal areas to 15 meters in depth. In general, they are not found in tide pools. The slimy sn...
www.inaturalist.org
October 16, 2025 at 11:28 AM
#FishADay Liparis mucosus Slimy Snailfish. NW Pacific coast. Up to 13cm, color varies from brown to red. Not to be confused w/ widespread orchid genus of same name, from Liparos, "oily" or "shiny"--leaves in orchid's case, whole critter in snailfish's case. www.inaturalist.org/taxa/223898-...
#FishADay Ethadophis byrnei Ordinary Eel. A snake eel originally known from a single specimen collected from the Gulf of California in 1967. A second specimen was reported from the Gulf of Tehuantepec in 2019. I guess it's not so ordinary...
aiep.pensoft.net/article/26915/
aiep.pensoft.net/article/26915/
First record of the ordinary eel, Ethadophis byrnei (Actinopterygii: Anguiliformes: Ophichthidae), in continental waters of the Gulf of Tehuantepec, Mexico: The southernmost occurrence in the eastern ...
The ordinary eel, Ethadophis byrnei Rosenblatt et McCosker, 1970, is newly recorded from the Mexican south Pacific coast, based on a single specimen captured inside a tropical coastal lagoon in the Gu...
aiep.pensoft.net
October 15, 2025 at 3:07 PM
#FishADay Ethadophis byrnei Ordinary Eel. A snake eel originally known from a single specimen collected from the Gulf of California in 1967. A second specimen was reported from the Gulf of Tehuantepec in 2019. I guess it's not so ordinary...
aiep.pensoft.net/article/26915/
aiep.pensoft.net/article/26915/
New notebook day! I've been keeping hard-copy research notes since I was an undergrad research assistant. My PI at the time told me, "You need to take good enough notes that if you are hit by a bus, someone can take over for you."
October 15, 2025 at 8:46 AM
New notebook day! I've been keeping hard-copy research notes since I was an undergrad research assistant. My PI at the time told me, "You need to take good enough notes that if you are hit by a bus, someone can take over for you."
#FishADay Ogcocephalus radiatus, Polka-Dot Batfish. Subtropical NW Atlantic coast. Highly modified to creep along seafloor, tricking prey into checking out a small, wiggly thing. "Hind legs" = pectoral fins, "front legs" = pelvic fins, lure over mouth = first dorsal fin spine. youtu.be/ubPOE4XJ85g
How Awesomely Different Looking Is The Polka Dot Batfish
YouTube video by Blue Heron Bridge Underwater Guide
youtu.be
October 14, 2025 at 12:36 PM
#FishADay Ogcocephalus radiatus, Polka-Dot Batfish. Subtropical NW Atlantic coast. Highly modified to creep along seafloor, tricking prey into checking out a small, wiggly thing. "Hind legs" = pectoral fins, "front legs" = pelvic fins, lure over mouth = first dorsal fin spine. youtu.be/ubPOE4XJ85g
#FishADay Stenodus nelma Inconnu aka Nelma. Arctic Ocean basin, mostly anadromous. Prefers waters under 16 C, gets up to 150 cm long. Prized sport fish (sometimes called "Arctic Tarpon") and subsistence food for native peoples of northwest Canada, Alaska, and Siberia.
youtu.be/8rBHYE4pB4I
youtu.be/8rBHYE4pB4I
Sheefish in Kotzebue
YouTube video by Alaska Native Tribal Health Consortium
youtu.be
October 13, 2025 at 12:50 PM
#FishADay Stenodus nelma Inconnu aka Nelma. Arctic Ocean basin, mostly anadromous. Prefers waters under 16 C, gets up to 150 cm long. Prized sport fish (sometimes called "Arctic Tarpon") and subsistence food for native peoples of northwest Canada, Alaska, and Siberia.
youtu.be/8rBHYE4pB4I
youtu.be/8rBHYE4pB4I
#FishADay Pagrus major Red Seabream. Western Pacific, mostly near reef bottoms. Highly-valued in several East Asian culinary traditions. In Japan, it's associated w/ luck & abundance; inspired street snack, taiyaki--basically a stuffed, fish-shaped waffle. upload.wikimedia.org/wikipedia/co...
October 9, 2025 at 12:23 PM
#FishADay Pagrus major Red Seabream. Western Pacific, mostly near reef bottoms. Highly-valued in several East Asian culinary traditions. In Japan, it's associated w/ luck & abundance; inspired street snack, taiyaki--basically a stuffed, fish-shaped waffle. upload.wikimedia.org/wikipedia/co...
#FishADay Periophthalmus barbarus Atlantic Mudskipper. Coastal tropical Africa. Spend most of their time on land, subsequently developed some unique adaptations to do things terrestrial tetrapods take for granted, like blinking--pulls its eyes into its head.
www.youtube.com/watch?v=twho...
www.youtube.com/watch?v=twho...
Mudskipper Blinking
YouTube video by Penn State University
www.youtube.com
October 7, 2025 at 2:23 PM
#FishADay Periophthalmus barbarus Atlantic Mudskipper. Coastal tropical Africa. Spend most of their time on land, subsequently developed some unique adaptations to do things terrestrial tetrapods take for granted, like blinking--pulls its eyes into its head.
www.youtube.com/watch?v=twho...
www.youtube.com/watch?v=twho...
#FishADay Pylodictis olivaris Flathead Catfish. FW from Great Lakes to Mexico. Reaches 150+ cm; closest living relative is a blind cave fish that reaches ~13 cm. Recent study documented reshuffling of food webs where it has invaded the Susquehanna www.wired2fish.com/news/invader...
Invader Alert: The New King of the Susquehanna
Invasive flathead catfish have taken over as the top predator on the Susquehanna River, leading to changes in the river’s ecosystem.
www.wired2fish.com
October 6, 2025 at 4:30 PM
#FishADay Pylodictis olivaris Flathead Catfish. FW from Great Lakes to Mexico. Reaches 150+ cm; closest living relative is a blind cave fish that reaches ~13 cm. Recent study documented reshuffling of food webs where it has invaded the Susquehanna www.wired2fish.com/news/invader...