Justin Waraniak
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marathon-rana.bsky.social
Justin Waraniak
@marathon-rana.bsky.social
380 followers 520 following 57 posts
Molecular ecologist, focusing on landscape genetics and conservation of freshwater ecosystems.
Postdoctoral Researcher, PA Fish & Wildlife Co-op at Penn State
he/him/they/them
Digital illustrator: www.marathonrana.com (Commissions Open)
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marathon-rana.bsky.social
Happy Pride! The diversity of life, in all its forms, is pretty rad!

(Side note: there's not a whole lot of purple fish, so the pink/silver goldeye is the best I got)

#SundayFishSketch #Pride
Six fish arrayed diagonally over the top of a rainbow pride flag. At the top left on the red stripe is a northern redbelly dace (Chrosomus eos), on orange is a male rainbow darter (Etheostoma caeruleum), a shorthead redhorse (Moxostoma macrolepidotum) on the yellow stripe, a northern pike (Esox lucius) for the green stripe, an orangespotted sunfish (Lepomis humilus) on the blue strip and a goldeye (Hiodon alosoides) on the purple stripe.
June 8, 2025 at 4:23 PM
Reposted by Justin Waraniak
jacsciart.bsky.social
I've been camping almost every weekend as of late so haven't been able to post #SundayFishSketch, but here is an edited version of my Rainbow Trout illustration with altered coloring in honor of #PrideMonth.
An illustration of a Rainbow Trout, but instead of the realistic coloring on the body, the colors make a rainbow in honor of Pride month.
June 7, 2025 at 11:39 AM
marathon-rana.bsky.social
I have a new paper out in Environmental Biology of Fishes on the effects of parasites on the life history of White Sands Pupfish! The two main findings being:

🧵(1/3)

rdcu.be/eptDZ
Life history trade-offs mediated by digene parasites in the protected White Sands pupfish (Cyprinodon tularosa)
rdcu.be
June 4, 2025 at 7:17 PM
marathon-rana.bsky.social
To celebrate the start of Pride Month, here are some Pride rainbow trout! Happy Pride everyone! #SundayFishSketch
Digital illustration of a rainbow trout, recolored with the colors of the bi pride flag, with dark blue on top, pink along the side, and deep magenta along the belly. Digital illustration of a rainbow trout recolored with the colors of the trans pride flag with light blue along the top and belly, pink along the sides, and a white stripe along the lateral line. Digital illustration of a rainbow trout recolored with the colors of the lesbian pride flag with oranges along the top, purples along the belly, and a white stripe along the lateral line.
June 1, 2025 at 3:37 PM
marathon-rana.bsky.social
A little late, but finished a least darter for #SundayFishSketch! The mating displays of this species may not be as intense as some other darters, but males of this species still develop bright red blotches on their fins!
Digital illustration of a breeding male least darter (Etheostoma microperca). This fish has a long oval-shaped body with a nearly rectangular tail that accounts for about a third of the length. It has a small mouth and dark stripes crossing the eye, one going from the top of the gill cover horizontally across the eye to the snout, the other starting just above the eye and continuing down across the cheek. It has two dorsal fins, the first spiny with sharp bony spines, the second soft supported by fan-like bony filaments. The tail fin is fan-shaped with no fork or distinct lobes. The anal fin has two sharp spines in the front before more soft rays arcing behind to make the rest of the fin. The pectoral and pelvic fins are large and very close together near the gill cover. The body is a mottled green-yellow color with dark brown splotches along the midline. There are bright red splotches on fin membrane between the rays of the first dorsal fin, pelvic fins, and anal fin.
May 26, 2025 at 3:17 PM
Reposted by Justin Waraniak
nicosgonzalez.bsky.social
USGS’ biological research arm could vanish next week www.hcn.org/articles/usg... via @highcountrynews.org
USGS’ biological research arm could vanish next week - High Country News
Trump is on a multipronged mission to eliminate a science agency that conservationists, toxicologists, universities and more call irreplaceable.
www.hcn.org
May 22, 2025 at 4:28 PM
Reposted by Justin Waraniak
drkatfish.bsky.social
Today (May 19) is the final day to provide comments on the Endangered Species Act rule change - here's some info about how to submit a comment: esa.org/esablog/2025...
May 19, 2025 at 5:18 PM
marathon-rana.bsky.social
Some old art of the Quitobaquito pupfish, an endangered species endemic to Organ Pipe Cactus National Monument and the Sonoyata River along the Arizona-Mexico border! #SundayFishSketch #CincoDeMayo
A digital illustration of a Quitobaquito pupfish (Cyprinodon eremus). This fish has a large head with a small mouth and a short, stout body. It has one trapezoidal dorsal fin along its back. The tail is very stout and the tail fin is shaped like a pentagon. There are small pectoral, pelvic, and anal fins along the fish's underside. This fish is bright blue in color with four darker teal bars along its back and a yellowish splotch on the upper side of the tail. The Mexican flag is in the background.
May 4, 2025 at 1:53 PM
marathon-rana.bsky.social
A johnny (the Baptist?) darter for this week's Easter-themed #SundayFishSketch! I was out doing some stream sampling this week and the darters were all colored up in their breeding colors, one of the surest signs of spring!
Digital illustrations of johnny darters, with the male breeding pattern shown in the upper left and the normal coloration in the bottom right. These fish have long cylindrical bodies and somewhat froglike faces with relatively small mouths and a gill cover that comes to a sharp point. They have two large dorsal fins along the back, the first with bony spines and the second with soft rays. The tail is fan-shaped and has no fork. The pectoral and pelvic fins are large and shaped like leaves. The breeding male has a dark grey head and belly, has dark stripes along the side of the body, and has dark grey fins with light colored rays and lots of dark spots. The normal coloration is more uniformly light brown with some small dark saddles on the back, markings in the shape of w's and x's along the side, and light colored fins with sparser spots. Both color morphs have a dark teardrop marking under the eye.
April 21, 2025 at 2:28 AM
Reposted by Justin Waraniak
jacsciart.bsky.social
Have been working on an illustration of Chiasmodon niger and decided to modify it a bit to fit today's #SundayFishSketch theme.
An in progress illustration of a Black Swallower fish. This fish lives in the deep sea and is brown to black in color with a long, thin body. It has a pretty large eye and very large mouth that leads to a stomach that can extend to several times its regular size, sometimes even becoming partly transparent. This allows the fish to eat prey larger than itself. In this illustration, I added some colorful Easter eggs in its stomach to fit with the Sunday Fish Sketch theme.
April 20, 2025 at 3:10 PM
Reposted by Justin Waraniak
jacsciart.bsky.social
The finished illustration of a Devil's Hole Pupfish.

#SciArt
An illustration of a Devil's Hole Pupfish. The fish is facing the left. The scales are a brown ochre color near the top of the fish, but are a sky blue along the sides, fading to a more cream color along the belly. Just below the eye, the coloring is more purple and pink, with some blue. The fins are almost white (supposed to represent clear) in color, but each has a black margin.
April 14, 2025 at 2:47 PM
marathon-rana.bsky.social
I feel like winter ice fishing is the prime season for catching burbot, and I live in the wrong part of the country to catch them now, but I always thought the eelpout festival in Minnesota looked kind of fun! #SundayFishSketch
Digital illustration of a burbot (Lota lota). This is a long eely fish closely related to cod. It has one long barbel on its chin. It has a small eye and a short, stout head. There are two dorsal fins on its back, the first short and roughly square shaped, and the second equal in height, but about four times as long. The anal fin is almost a direct mirror of the second long dorsal fin, just on the bottom side of the fish. The tail fin is comparatively small and round in shape. The pelvic fins and pectoral fins are similarly shaped, very close together, and positioned just behind the gill cover. The body of the fish is covered in tiny scales that are barely visible. The belly of the fish is a light cream in color, while the top side and the fins are covered in yellowish-orange splotches on a mottled dark brown background.
April 13, 2025 at 8:48 PM
Reposted by Justin Waraniak
liseviollat.bsky.social
I made a little mini zine about eels hehehe
#sundayfishsketch
April 13, 2025 at 7:08 PM
Reposted by Justin Waraniak
jasonkeagy.bsky.social
This is a bit delayed because I’ve been distracted by the world going to shit, but…

We published a paper that I am so very excited about: doi.org/10.1016/j.sc...

In this study we tracked brook trout response to heat waves in nature using gene expression from non-lethal gill biopsies. (1/n)
Redirecting
doi.org
April 9, 2025 at 9:26 PM
marathon-rana.bsky.social
It was the trout season opener this weekend in Pennsylvania, so to celebrate here's a brown trout! #SundayFishSketch
Digital illustration of a brown trout (Salmo trutta). This fish has a torpedo-shaped body with a large mouth. The lower jaw is longer than the upper jaw. It has one rectangular dorsal fin and a small round adipose fin on its back. The tail is wide and very slightly forked. The body is brown with some orange and yellow highlights and is covered in dark red and brown spots of varying sizes, some with light colored outlines. The whole body is covered in very small scales.
April 7, 2025 at 3:41 AM
marathon-rana.bsky.social
Inking some spots for the next fish I'm working on. Any guesses on who they belong to?

#SundayFishSketch #WIP
Closeup of a work in progress digital illustration of a fish. The close-up only shows the side of the fish, with no fins or parts of the head visible. The field of the fish's body is an orange-brown, darker on top with a brighter yellow cream color on the bottom. There are also tons of spots, some larger brownish-red ones with light colored outlines, smaller densely packed dark grey spots, and even smaller sparse bright red spots.
March 30, 2025 at 3:54 PM
marathon-rana.bsky.social
I'm really excited to share our most recent paper on gene expression in wild populations of brook trout in response to heatwaves! We identified candidate biomarkers of heat stress and tracked changes across the whole transcriptome in multiple populations. (1/5)

www.sciencedirect.com/science/arti...
Graphical abstract for a study about the transcriptomic response of brook trout to heat stress. The abstract starts with an illustration of a brook trout in the upper left, with a cutout zooming into an illustration of the fish's red stringy gill filaments. An arrow points from the gill filaments to an illustration of mRNA molecules. Next to the fish illustration is a chart tracking temperature during the study with date on the x-axis (from July 15 to August 15) and daily high temperatures showing two roughly week long periods of elevated temperatures (>20ºC), each followed by periods of cooler temperatures (~18ºC). A text box below the graph reads: "Brook trout (N=116) gill samples were collected 8 times across 4 streams over the course of successive heatwaves. Gill mRNA was sequenced using TagSeq." The abstract continues with a summary of the results. "Potential biomarkers tracked temperature" appears over a series of graphs that overlay the expression levels of a heat shock protein on top of the temperature trends in each stream through time. The lines tracking temperature and the amount of heat shock protein mRNA look very similar. "Trajectory analysis tracked changes in the whole transcriptome through time" appears above a graph describing how expression changed during each of the sampled time points along two principal component axes. A text box to the right reads: "Results: 43 temporally differentially expressed genes detected. Most patterns in the transcriptomic response were conserved among streams. Significant differences in expression patterns between streams for many differentially expressed genes and multivariate metrics of whole transcriptome changes." "Gene functions found in multiple analyses" appears above three illustrations, a thermometer representing heat shock proteins, red blood cells representing oxygen binding, and a T-cell representing the immune response.
March 18, 2025 at 6:17 PM
marathon-rana.bsky.social
I re-drew a common shiner for this week's #SundayFishSketch! This was one of the first fish I drew while figuring out my digital art workflow, and it's fun to see how my style has developed over the years! #redraw
Two digital illustrations of common shiners, the more recent one in the upper left and the older one in the lower right. Both have deep fusiform bodies, large eyes, red bellies, and red tips on all the fins. Both are also covered in tall shiny diamond-shaped scales. The main differences are that the older lower illustration has a high-contrast dark colored back and very simply drawn light-colored eye, while the newer drawing has a more naturalistic lower contrast dark silver back, a more detailed dark colored eye, and a series of small breeding tubercles on the top of its head.
March 16, 2025 at 8:55 PM
marathon-rana.bsky.social
Finished a flathead chub for this week's #SundayFishSketch!
Side profile digital illustration of a flathead chub (Platygobio gracilis). This fish has a fairly long pointed snout with a short lower jaw. There is a small barbel hanging off the upper lip near the corner of the mouth. This fish has one concave dorsal fin midway down its body. The tail fin is deeply forked and there is a dark black edge along the bottom of the lower lobe. The body is a dusky greyish pink and covered in fairly large shiny scales.
March 9, 2025 at 5:03 PM
marathon-rana.bsky.social
Did you know: NOAA manages US marine fisheries, including the fisheries in the Great Lakes! So if you like having sustainable local fisheries, thank NOAA scientists (and maybe advocate against the indiscriminate firing policies pushed by power-crazed billionaires).

#SundayFishSketch #LakeWhitefish
Digital illustration of a lake whitefish. This fish is closely related to salmon and has a similar body shape. The mouth is small and opens beneath the snout. The fish has one short square-ish dorsal fin halfway down its back and a small circular adipose fin closer to the tail. The tail is robust and the tail fin is very deeply forked. The body is a dusky greenish gray, darker on top and lighter on the belly. It is covered in hundreds of small shiny scales.
March 2, 2025 at 5:07 PM
marathon-rana.bsky.social
This is devastating. One of the goals of REU programs is to provide opportunities for underrepresented groups. REUs were the way I got my foot in the door to do research and figured out that I liked working in genetics. Gutted for the students affected by this.
standupforscience.bsky.social Stand Up for Science! @standupforscience.bsky.social · Feb 24
🚨 Many NSF-funded Research Experiences for Undergraduates (REUs) are being cancelled for Summer 2025.

www.reddit.com/r/REU/commen...
Cancellation megathread
www.reddit.com
February 24, 2025 at 9:12 PM
Reposted by Justin Waraniak
jacsciart.bsky.social
I finally finished my Spotted Gar illustration for today's #SundayFishSketch 🐡
An illustration of a Spotted Gar. The fish is long and thin, with a long, thin nose. The back is a darker olive-brown, and fades to pale cream towards the belly. The fins have a slight orange-red hue to them, and the body of the fish is covered in dark, irregular spots.
February 23, 2025 at 3:45 PM
Reposted by Justin Waraniak
drkatfish.bsky.social
Calling all budding artists! This year's Wildlife Forever Fish Art Contest has a #GreatLakes Fish specialty award. K-12 students are eligible. And who doesn't want the chance to win a model of a sea lamprey?! Submissions are due Feb. 28 #sciart www.theartofconservation.org/great-lakes-...
A screenshot of the requirements for the Great Lakes Fish Prize for an annual Fish Art contest. The text has a list of fish species from the Great Lakes. A screenshot of the prizes for winning the Great Lakes specialty award.
February 20, 2025 at 1:18 PM
Reposted by Justin Waraniak
amfisheriessoc.bsky.social
Today, we share our love for federal #fisheries professionals who work tirelessly to address the myriad problems facing our nation’s fisheries. We urge the Administration to stop indiscriminate mass firings and to build and maintain a sufficient federal natural resource workforce.
A pink box with heart border and text reading, "We Love Our Federal Fisheries Workforce! Federal fisheries professionals are American heroes who safekeep our fisheries and aquatic resources for all of us."
February 14, 2025 at 7:27 PM
marathon-rana.bsky.social
Since it's the Super Bowl, here's a repost of a carmine shiner, native to the KC area (and that I drew for the Chiefs last year 😞) and a brook trout, the state fish of Pennsylvania! Go Birds I guess? #SundayFishSketch
Digital illustration of a carmine shiner. This minnow has a slender, torpedo-shaped body. It has a large eye and a fairly large mouth that extends underneath the front of the eye. It has a single small dorsal fin, a moderately forked tail, and a trapezoidal anal fin. The body is mostly olive brown, but there are hints of red on the head, the belly, along the lateral line, and at the origins of the fins. A digital illustration of a brook trout. This fish has a triangular head with a very large mouth that extends well past the eye. The body is torpedo-shaped with a rectangular dorsal fin and small round adipose fin on the top. The tail is fan-shaped with a small notch at the fork. The pectoral, pelvic, and anal fins are bright red-orange, except the leading edges which are white with a black border. The body is mostly green with bright yellow spots and small blue and red bullseye patterns across the sides. The coloration along the back has squiggly yellow shapes instead of spots.
February 10, 2025 at 1:48 AM