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Today's fish of the day is the arctic grayling trout!

The arctic grayling trout, scientific name Thymallus arcticus, was requested by Rion! I am always taking fish suggestions, so feel free to message with them! Native to North America, and other areas in the arctic. This fish can mostly be found in Alaskan rivers, branching further into Canada, and across the arctic. Some populations have found their ways into rivers and lakes across the rocky mountains and into the Great Lakes of Michigan. And although this fish is not native to the Columbia basin, or the Mississippi, but has been found in both in the past. They can be found only in cold, clear water, and although coloration changes from population to population, they can be identified by the red fringe across the dorsal fin.

Arctic graylings can be found only in cold, clear water, and although coloration changes from population to population, they can be identified by the red fringe across the dorsal fin. The arctic grayling's diet consists of small fish and insects. Although, they're not picky and will eat anything that will fit in their mouth. This diet supports them reaching around 30 inches in length, and about 8 pounds. They are predated on by fish eating birds, larger fish, and mammals that catch them.

Spawning takes place in the spring, and only in areas with a fine sandy bottom, and a slow to moderate current. Courting is done by flashing the dorsal fins, and mates are chosen often by the starkest color. Eggs are then left behind, and will hatch within 2 weeks. Arctic graylings grow up quickly, and will reach sexual maturity within 2 years of hatching.

Today's fish of the day is the Wahoo, known by the scientific name Acanthocybium solandri! These fish are well known for the high quality of their meat, and their high speeds, regularly compared to tuna in terms of speed and agility. Visually, these fish have been mixed up with barracuda and king mackerel or spanish mackerel. Distinction between wahoo and mackerels being found in a flap of skin covering the mandible when the mouth is closed in the wahoo. Barracuda is distinguishable from both the wahoo and mackerels due to differing scale sizes and teeth shapes. 

Wahoo have two distinct species, the Atlantic wahoo and the Pacific wahoo, which can hybridize and are thought to be visually identical. Wahoo grow fast, getting as large as 8ft in full adulthood, and weighing as much as 160 pounds. Both males and females reach secual materity at 1 year, although by this point they are only about 3ft long on average, it will take another 2 years for them to reach their full size. Their eggs are buoyant, and although Wahoo rarely exist in schools, preferring to exist in small groups or simply alone, they will gather in large groups for spawning.  When born, the larvae and fry stay in the pelagic zone. Adults also prefer to remain close to the surface, but dive deeper for hunting, or in pursuit of food. 

The diet consists mostly of fishes, oftentimes, schooling fishes. Although those in the Atlantic are known to have a penchant for cephalopods. Often, wahoo are in direct competition with tuna for food, but they have an advantage with their sharper teeth. Younger wahoo are preyed on by large fish, and adults are preyed on by sharks, other than that, they are relatively unbothered in the waters. Wahoo's habitat lies along tropical and subtropical waters, and although migration routes are currently unknown, they are regularly found at higher latitudes in the summer months. These fish can exist in almost every environment, but they prefer to live along banks, and closer to shores, although they can be found in the open ocean just as easily.

Happy Thursday, everyone! Today's fish of the day is the Australian lungfish!

The Australian lungfish, or barramunda, known by scientific name Neoceratodus forsteri is one of the 6 surviving lungfishes of the modern world. The other 5 lungfishes are scattered to other sections of the world, one in South America, and the other 4 all living in Africa. As the name implies, this lungfish is endemic to Australia living in South Eastern Queensland, or for those who don't know the general areas of Australia, the upper right corner of the country. Living exclusively in slow moving streams, still waters, and various waterside banks living entirely in freshwater systems. This fish is primarily nocturnal, and almost entirely carnivorous. Its diet consists of: frogs, larvae, bugs, plant material, earthworms, fishes, small invertebrates, and anything else it can catch.  They are primarily bottom dwellers, and prey is caught directly in the mouth and then crushed multiple times, being positioned correctly by a bone called a hydroid apparatus. Australian lungfish have the most primitive of surviving lungfish feeding behaviors.

Australian lungfish are best known for their ability to survive dry seasons. However, unlike African lungfish, which can survive fully in droughts by submerging themselves into  This is done by submerging the body in the mud, and rising to the surface to swallow oxygen into a single dorsal lung. This lung is only supplementary, and the fish prefer to breathe through their 5 gills. Of the six lungfish, the Australian lungfish is the only one to not have two lungs, but rather a fold down the center of the single lung acting as a wall, which blood capillaries run through, allowing gas exchange. Unlike it's African counterparts, the Australian lungfish can not survive total water depletion, (other lungfish survive this by creating a layer of mucus around itself and living there for several years until water returns). Australian lungfish can survive several days out of the water, but can not do so unless it is in a moist environment, usually mud.

Fossil records of lungfish tell us that some of their first fossils can be found from 410 Million years ago, being the closest living relative to the tetrapod. The last shared ancestor between the lungfish and tetrapod was 420 Million year ago. Originally, these animals started as marine creatures, but sometime in the carboniferous the species became freshwater exclusive, around the same time that the last common ancestor to all remaining lungfish lived.  Australian lungfish in particular appear to have split off about 380 million years ago, and have remained virtually unchanged from their ancestors for over 100 million years, giving them the title of living fossils! 

Not only have they remained incredibly similar over the years, they have a long lifespan for individuals as well. A captive Australian lungfish named granddad was shown to live to 108 years (+- 6), with the expected lifespan of wild lungfish surviving at least 20-25 years after they reach sexual maturity. In Australian lungfish, similar to other lungfish species in the world, sexual maturity is reached in males after 17 years, and 22 years in females. Australian lungfish have elaborate courting rituals consisting of three distinct phases. The first phase is searching, where the lungfish will breathe loudly, making mating calls with its single lung. The second is called "follow the leader" where males will attempt to entice a female by nudging and rubbing snouts with her, often at the same time as competitors. The last stage is where two lungfish will descend to lay and fertilize eggs, females producing 2 eggs per spawning season. After breeding, the eggs are left to sink in the vegetation, as Australian lungfish do not nest or care for their young. This is unlike all other lungfish species.

The fish of the day today is the devils hole pupfish!

The devils hole pupfish, scientific name Cyprinodon diabolis, is an endangered fish known to live in exactly one spot, Devils hole. Devils hole is a limestone cavern with a geothermal pool found in Nye county of Nevada, and a disconnected section of Death Valley National Park. The geothermal pool keeps the water at a consistent 33 degrees Celsius all seasons, and has low dissolved oxygen amounts. The surface of water at the cave is only 72ft by 12ft, but below that the cave descends deep into the earth. Below the surface pool there is a larger cavern descending to 150 meters at its deepest before branching into a smaller tube at the bottom, the depth of which is currently unknown.1965 two teenagers went diving in the hole with scuba gear, and were never seen again,  rescue divers sent after them found a dropped flashlight, and other scuba gear but the bodies were never found. One rescue diver dropped a weighted plate that fell a full 932ft without contacting a bottom to the chamber, describing the water below him as an "infinity chamber". Later scans of the cave revealed it is at least as deep as 1,247ft, although to this day the depth is still unknown. Another well known aspect of the cave is that it can be used to determine when there are earthquakes all over the world. The water surges and has displayed unique patterns during the 2022 Mexico 7.6 magnitude earthquake, along with other strong earthquakes further from the hole. Such as: the 2012 6.2 magnitude earthquake in Papua New Guinea, or the 2018 7.4 magnitude earthquake in Indonesia. Devils hole pupfish are known to live only in the first 80ft of the cave.

Devils hole pupfish are unique in appearance, getting only as large as an inch, and being one of few species that have no pelvic fins, however when raised in colder conditions these pupfish will regrow these appendages. As juveniles these fish are an off white color, and females retain some of this coloring in adulthood. This species has only ever been recorded with as many as 500 wild fish at its highest, hitting an all time low point of 42 fish in 2007. The more recent numbers are looking up however, and there were 263 pupfish observed in spring of 2022. The survival from egg to adulthood is small, but the likelihood with human effort that this fish will survive the test of time is high. Described as possibly the most isolated wild vertebrate species in the world. These fish live only 10-14 months, reaching sexual maturity at 8-10 weeks old and spawn year round with peaks in mid February-May, and a smaller peak in July-September. Due to the unique oxygen levels of devils hole, these fish have adapted to enter a state of tupor, similar to hibernation, where they can live anaerobically. This allows them to go without breathing for up to 2 hours, however they produce ethanol as a byproduct.

Most of the devils hole pupfish life is on the rocky outcrops of the surface waters of the cave system. Breeding, egg laying, diet, resting, and schedules surrounding the placement of the sun all depend on these rocky outcroppings of stone near the surface of the water. The diet of these fish is dependent on the rock outcroppings of the cave, as they eat anything they can find in the cave system. This includes: small freshwater crustaceans, beetles, flatworms, freshwater snails, inorganic matter made of small sections of the caves limestone, along with spirogyra and diatom algae, which grows on the rocks themselves and makes up most of the pupfish's diet. Due to their diet being mostly algae types, pupfish are incredibly susceptible to the seismic activity in the devils' hole, as it creates small tsunamis along surface water and washes away algae on the rocks, leaving them without a majority of their food source until it regrows. When these earthquakes happen the pupfish are known to flee into the deer waters of the cave until the water has stilled, and are thought to perhaps feel earthquakes before they happen, although not much research has been done on this yet.

Today's fish of the day is the candy darter!

The candy darter, known by scientific name Etheostoma osburni, is an endangered fish endemic to the East coast of America. Living in the Kanawha River, which is a tributary of the Ohio river, and flows through the Appalachian mountains, winding through Virgina, with a majority in West Virginia. Identifiable from the lookalikes likely to be found in the same general areas by the distinct saddles in front of the dorsal fin, and by the number of blue and orange bars on the fish. Despite the wonderfully bright color of the males, there is a significant case of sexual dimorphism, with the females of this species bearing the same marking but in a much cooler olive color.

Described in 1932, these fish are a rare find in freshwater areas of North America, being described as "[possibly] the most vivid freshwater fish in North America"- by A Field Guide to Freshwater Fishes, Page and Burr 1991. These fish used to have a historic range across 37 known sites, but can now be found in only 10, being impacted greatly by human interference. The biggest issue these fish face is the introduction of a second species of darter, the variegate darter (Etheostoma variatum) which is thought to have been introduced into the area by bait bucket dumping into streams. These fish are able to hybridize, and offspring are closer to variegate darter, than their cander darter parents, overtime wiping out candy darters from their natural habitats. Habitat loss is also a worry for these fish, as they rely on pure and unsalted waters and clean gravel to lay eggs on. But, hope remains for the fate of these fish. Conservation efforts for candy darters are well underway, and the ability to save these species is still very possible.

Candy darters can get as large as 4 inches, and have a lifespan of 3 years. Only hitting sexual maturity at about year 2. Their spawning season is April-May and is in a preferred temperature of 15-18 degrees C. Females during this season are bound to the river bottom as they brood hide, choosing only to lay eggs on fine pebbles and gravel. This is why excess sediment in rivers like this is such a huge concern for this species. During this breeding season male candy darters become aggressive and infight for the ability to fertilize eggs, leaving only the largest and most successful males the ability to pass their genes forward

During their lifespan the diet of the candy darter consists of macro-invertebrates. Mostly flies, caddisflies, mayflies, and larvae that they can get their hands on. Later in their life, they will be eaten by larger fish primarily. Along with these, these fish are known for their ability to help the reproduction of freshwater mussel species. This helps keeps river clear

Today's fish of the day is the mangrove horseshoe crab!

The mangrove horseshoe crab, also known as the round-tailed horseshoe crab, and scientific name Carcinoscorpius rotundicauda is one of the four living species of horseshoe crab remaining. The mangrove Horseshoe crab is closely related to the other 2 Asian horseshoe crabs: The Indo-Pacific Horseshoe crab (Tachypleus gigas), and the Chinese Horseshoe crab (Tachypleus tridentatus), but is the only member of the Carcinoscorpius genus. These three horseshoe crabs are separate from the American Atlantic Horseshoe crab, which separated between 130 to 400 million years ago! Now, Horseshoe crabs are horribly named, as they're not crabs at all. Instead, they belong to subphylum Chelicerata, which is in the Arthropod phylum, directly relating them to spiders and ticks.

Like its name implies, the mangrove horseshoe crab lives in brackish waters in mangrove forests. They can be found across Southeastern Asia, down to the Indo-Pacific in Tropical and subtropical climates. This animal spends its time in shallow waters, preferring sandy areas. The mangrove Horseshoe is benthopelagic, meaning it lives its life on the seafloor, and although they rarely do so, horseshoe crabs can swim, albeit, upside down. I'd recommend looking up a video on them swimming, it's very cool to see!

As benthic creatures, the mangrove horseshoe crabs diet is limited to what it can find on the seabed. Not only that, but, like all parts of the Chelicerata subphylum, it lacks jaws and teeth, and so it must feed in another method. Horseshoe crabs eat by grabbing prey with chelicerae, a pair of appendages in front of its legs, and passing prey to a food grove that runs from the furthest back legs, and up to the mouth. Well in the food grove, the bases of the legs are used to grind prey with teeth like structures, simultaneously passing further forward. Due to horseshoe crabs being so unchanged over the years, it is thought that this feeding method may have belonged to some of the earliest Arthropods. The diet of the mangrove horseshoe crab in particular is made up of insect larvae, small fish, marine worms, and mollusks. Although mangrove horseshoe crabs in particular have a strong preference for insect larvae above other prey.

Anatomically horseshoe crabs get stranger yet. They contain 10 eyes: 2 compound eyes, which can be seen on the top of the head, used primarily for finding mates. Then, there is a pair of lateral eyes, on the underside, ventral eyes, used for finding prey, an endoparetial eye, and median eyes. Horseshoe crabs can see both visible and ultraviolet light, but are particularly sensitive to light amounts and changes in their surroundings. The tail, as opposed to some common thought, is not poisonous or a weapon, but rather it is used for flipping over easily, and some movement well swimming. In Mangrove horseshoe crabs the tail is far more rounded than its relatives.

Today's fish of the day is the mangrove horseshoe crab!

The mangrove horseshoe crab, also known as the round-tailed horseshoe crab, and scientific name Carcinoscorpius rotundicauda is one of the four living species of horseshoe crab remaining. The mangrove Horseshoe crab is closely related to the other 2 Asian horseshoe crabs: The Indo-Pacific Horseshoe crab (Tachypleus gigas), and the Chinese Horseshoe crab (Tachypleus tridentatus), but is the only member of the Carcinoscorpius genus. These three horseshoe crabs are separate from the American Atlantic Horseshoe crab, which separated between 130 to 400 million years ago! Now, Horseshoe crabs are horribly named, as they're not crabs at all. Instead, they belong to subphylum Chelicerata, which is in the Arthropod phylum, directly relating them to spiders and ticks.

Like its name implies, the mangrove horseshoe crab lives in brackish waters in mangrove forests. They can be found across Southeastern Asia, down to the Indo-Pacific in Tropical and subtropical climates. This animal spends its time in shallow waters, preferring sandy areas. The mangrove Horseshoe is benthopelagic, meaning it lives its life on the seafloor, and although they rarely do so, horseshoe crabs can swim, albeit, upside down. I'd recommend looking up a video on them swimming, it's very cool to see!

As benthic creatures, the mangrove horseshoe crabs diet is limited to what it can find on the seabed. Not only that, but, like all parts of the Chelicerata subphylum, it lacks jaws and teeth, and so it must feed in another method. Horseshoe crabs eat by grabbing prey with chelicerae, a pair of appendages in front of its legs, and passing prey to a food grove that runs from the furthest back legs, and up to the mouth. Well in the food grove, the bases of the legs are used to grind prey with teeth like structures, simultaneously passing further forward. Due to horseshoe crabs being so unchanged over the years, it is thought that this feeding method may have belonged to some of the earliest Arthropods. The diet of the mangrove horseshoe crab in particular is made up of insect larvae, small fish, marine worms, and mollusks. Although mangrove horseshoe crabs in particular have a strong preference for insect larvae above other prey.

Anatomically horseshoe crabs get stranger yet. They contain 10 eyes: 2 compound eyes, which can be seen on the top of the head, used primarily for finding mates. Then, there is a pair of lateral eyes, on the underside, ventral eyes, used for finding prey, an endoparetial eye, and median eyes. Horseshoe crabs can see both visible and ultraviolet light, but are particularly sensitive to light amounts and changes in their surroundings. The tail, as opposed to some common thought, is not poisonous or a weapon, but rather it is used for flipping over easily, and some movement well swimming. In Mangrove horseshoe crabs the tail is far more rounded than its relatives.

Today's fish of the day is the mangrove horseshoe crab!

The mangrove horseshoe crab, also known as the round-tailed horseshoe crab, and scientific name Carcinoscorpius rotundicauda is one of the four living species of horseshoe crab remaining. The mangrove Horseshoe crab is closely related to the other 2 Asian horseshoe crabs: The Indo-Pacific Horseshoe crab (Tachypleus gigas), and the Chinese Horseshoe crab (Tachypleus tridentatus), but is the only member of the Carcinoscorpius genus. These three horseshoe crabs are separate from the American Atlantic Horseshoe crab, which separated between 130 to 400 million years ago! Now, Horseshoe crabs are horribly named, as they're not crabs at all. Instead, they belong to subphylum Chelicerata, which is in the Arthropod phylum, directly relating them to spiders and ticks.

Like its name implies, the mangrove horseshoe crab lives in brackish waters in mangrove forests. They can be found across Southeastern Asia, down to the Indo-Pacific in Tropical and subtropical climates. This animal spends its time in shallow waters, preferring sandy areas. The mangrove Horseshoe is benthopelagic, meaning it lives its life on the seafloor, and although they rarely do so, horseshoe crabs can swim, albeit, upside down. I'd recommend looking up a video on them swimming, it's very cool to see!

As benthic creatures, the mangrove horseshoe crabs diet is limited to what it can find on the seabed. Not only that, but, like all parts of the Chelicerata subphylum, it lacks jaws and teeth, and so it must feed in another method. Horseshoe crabs eat by grabbing prey with chelicerae, a pair of appendages in front of its legs, and passing prey to a food grove that runs from the furthest back legs, and up to the mouth. Well in the food grove, the bases of the legs are used to grind prey with teeth like structures, simultaneously passing further forward. Due to horseshoe crabs being so unchanged over the years, it is thought that this feeding method may have belonged to some of the earliest Arthropods. The diet of the mangrove horseshoe crab in particular is made up of insect larvae, small fish, marine worms, and mollusks. Although mangrove horseshoe crabs in particular have a strong preference for insect larvae above other prey.

Anatomically horseshoe crabs get stranger yet. They contain 10 eyes: 2 compound eyes, which can be seen on the top of the head, used primarily for finding mates. Then, there is a pair of lateral eyes, on the underside, ventral eyes, used for finding prey, an endoparetial eye, and median eyes. Horseshoe crabs can see both visible and ultraviolet light, but are particularly sensitive to light amounts and changes in their surroundings. The tail, as opposed to some common thought, is not poisonous or a weapon, but rather it is used for flipping over easily, and some movement well swimming. In Mangrove horseshoe crabs the tail is far more rounded than its relatives.

Today's fish of the day is the candy darter!

The candy darter, known by scientific name Etheostoma osburni, is an endangered fish endemic to the East coast of America. Living in the Kanawha River, which is a tributary of the Ohio river, and flows through the Appalachian mountains, winding through Virgina, with a majority in West Virginia. Identifiable from the lookalikes likely to be found in the same general areas by the distinct saddles in front of the dorsal fin, and by the number of blue and orange bars on the fish. Despite the wonderfully bright color of the males, there is a significant case of sexual dimorphism, with the females of this species bearing the same marking but in a much cooler olive color.

Described in 1932, these fish are a rare find in freshwater areas of North America, being described as "[possibly] the most vivid freshwater fish in North America"- by A Field Guide to Freshwater Fishes, Page and Burr 1991. These fish used to have a historic range across 37 known sites, but can now be found in only 10, being impacted greatly by human interference. The biggest issue these fish face is the introduction of a second species of darter, the variegate darter (Etheostoma variatum) which is thought to have been introduced into the area by bait bucket dumping into streams. These fish are able to hybridize, and offspring are closer to variegate darter, than their cander darter parents, overtime wiping out candy darters from their natural habitats. Habitat loss is also a worry for these fish, as they rely on pure and unsalted waters and clean gravel to lay eggs on. But, hope remains for the fate of these fish. Conservation efforts for candy darters are well underway, and the ability to save these species is still very possible.

Candy darters can get as large as 4 inches, and have a lifespan of 3 years. Only hitting sexual maturity at about year 2. Their spawning season is April-May and is in a preferred temperature of 15-18 degrees C. Females during this season are bound to the river bottom as they brood hide, choosing only to lay eggs on fine pebbles and gravel. This is why excess sediment in rivers like this is such a huge concern for this species. During this breeding season male candy darters become aggressive and infight for the ability to fertilize eggs, leaving only the largest and most successful males the ability to pass their genes forward

During their lifespan the diet of the candy darter consists of macro-invertebrates. Mostly flies, caddisflies, mayflies, and larvae that they can get their hands on. Later in their life, they will be eaten by larger fish primarily. Along with these, these fish are known for their ability to help the reproduction of freshwater mussel species. This helps keeps river clear

The fish of the day today is the devils hole pupfish!

The devils hole pupfish, scientific name Cyprinodon diabolis, is an endangered fish known to live in exactly one spot, Devils hole. Devils hole is a limestone cavern with a geothermal pool found in Nye county of Nevada, and a disconnected section of Death Valley National Park. The geothermal pool keeps the water at a consistent 33 degrees Celsius all seasons, and has low dissolved oxygen amounts. The surface of water at the cave is only 72ft by 12ft, but below that the cave descends deep into the earth. Below the surface pool there is a larger cavern descending to 150 meters at its deepest before branching into a smaller tube at the bottom, the depth of which is currently unknown.1965 two teenagers went diving in the hole with scuba gear, and were never seen again,  rescue divers sent after them found a dropped flashlight, and other scuba gear but the bodies were never found. One rescue diver dropped a weighted plate that fell a full 932ft without contacting a bottom to the chamber, describing the water below him as an "infinity chamber". Later scans of the cave revealed it is at least as deep as 1,247ft, although to this day the depth is still unknown. Another well known aspect of the cave is that it can be used to determine when there are earthquakes all over the world. The water surges and has displayed unique patterns during the 2022 Mexico 7.6 magnitude earthquake, along with other strong earthquakes further from the hole. Such as: the 2012 6.2 magnitude earthquake in Papua New Guinea, or the 2018 7.4 magnitude earthquake in Indonesia. Devils hole pupfish are known to live only in the first 80ft of the cave.

Devils hole pupfish are unique in appearance, getting only as large as an inch, and being one of few species that have no pelvic fins, however when raised in colder conditions these pupfish will regrow these appendages. As juveniles these fish are an off white color, and females retain some of this coloring in adulthood. This species has only ever been recorded with as many as 500 wild fish at its highest, hitting an all time low point of 42 fish in 2007. The more recent numbers are looking up however, and there were 263 pupfish observed in spring of 2022. The survival from egg to adulthood is small, but the likelihood with human effort that this fish will survive the test of time is high. Described as possibly the most isolated wild vertebrate species in the world. These fish live only 10-14 months, reaching sexual maturity at 8-10 weeks old and spawn year round with peaks in mid February-May, and a smaller peak in July-September. Due to the unique oxygen levels of devils hole, these fish have adapted to enter a state of tupor, similar to hibernation, where they can live anaerobically. This allows them to go without breathing for up to 2 hours, however they produce ethanol as a byproduct.

Most of the devils hole pupfish life is on the rocky outcrops of the surface waters of the cave system. Breeding, egg laying, diet, resting, and schedules surrounding the placement of the sun all depend on these rocky outcroppings of stone near the surface of the water. The diet of these fish is dependent on the rock outcroppings of the cave, as they eat anything they can find in the cave system. This includes: small freshwater crustaceans, beetles, flatworms, freshwater snails, inorganic matter made of small sections of the caves limestone, along with spirogyra and diatom algae, which grows on the rocks themselves and makes up most of the pupfish's diet. Due to their diet being mostly algae types, pupfish are incredibly susceptible to the seismic activity in the devils' hole, as it creates small tsunamis along surface water and washes away algae on the rocks, leaving them without a majority of their food source until it regrows. When these earthquakes happen the pupfish are known to flee into the deer waters of the cave until the water has stilled, and are thought to perhaps feel earthquakes before they happen, although not much research has been done on this yet.