Articles tagged with Ichthyology
A rare opportunity to study how a critically endangered species copes with an earthquake- induced tsunami has been provided by researchers. The Devils Hole pupfish inhabit a small, shallow pool in the Mojave Desert, and the quake's impact on their habitat and behavior was documented on camera.
A new antifouling substance, medetomidine, has been shown to cause paler fish by affecting their skin cells containing dark pigment. The research also found that the substance can impair a fish's ability to break down environmental toxins and affect its liver function.
Researchers found trawl fish landings peaked in 1937 at 14 times higher than today and bottom-living fish availability fell by 94%. The decline in popular fish stocks such as cod, haddock, and plaice is more profound than previously thought. The study suggests a longer period of damage to fisheries has taken place
Researchers found that sharks in deep waters of El Cachucho feed on small crustaceans and fish, adapting to changing ocean depths. Understanding their diet helps predict changes in trophic networks and monitor species populations.
Researchers found that coastal and open-ocean fish have distinct mercury signatures, ruling out the idea that they pick up methylmercury by eating contaminated coastal fish. Instead, they suggest that mercury is deposited into the open ocean and undergoes methylation in low-oxygen microenvironments.
A Purdue University study has found that nanosilver, a bactericidal agent, is toxic to fish and can cause malformations even at low concentrations. Researchers detected nanoparticles as small as 30 nanometers inside fish embryos, highlighting the need for further testing on environmental release levels.
Researchers are working with commercial fishermen to track monkfish migration patterns using electronic tags implanted under the skin. The study aims to improve understanding of the fish's biology and behavior, including its age and growth rate, as well as its interaction with ocean currents and tides.
A recent study published in the Proceedings of the National Academy of Sciences challenges the long-held notion that fish obtain up to 50% of their carbon from terrestrial sources. Instead, researchers found that algae provide a much more nutritious and abundant diet for fish and other aquatic life.
Prosta Chakrabarty, an LSU ichthyologist, has landed a major grant to reconstruct the genetic heritage of heroine cichlid fishes. He also discovered two new species of angler fishes native to Louisiana, shedding light on the planet's history and biodiversity.
Researchers mapped the sex chromosomes of cichlid fish from Lake Malawi and identified a mechanism for evolving new sex chromosomes. A genetic conflict over color patterns led to the emergence of new sex determining functions, resulting in distinct sex chromosomes among related species.
A large prospective population study found no difference in heart failure risk between fish eaters and non-eaters. However, a beneficial effect was observed in diabetic subjects with high EPA + DHA intake.
Oceanographers at University of Hawaii at Manoa found that deeper pelagic fish have higher mercury concentrations due to their unique diets. The study, published in the Proceedings of the National Academy of Sciences, highlights the importance of understanding the open ocean ecosystem to sustainably manage fish populations.
The team aims to create biologically inspired material systems that can intelligently sense and actuate a network of distributed robust sensors and actuators. They will develop a robotic fish-like underwater vehicle by integrating biological investigations of fish with engineering knowledge about sensors and actuators.
A recent study published in the American Journal of Clinical Nutrition found an inverse association between fish consumption and dementia prevalence in older adults across 7 middle- to low-income countries. Higher fish consumption was linked to a lower risk of dementia, contradicting previous findings from industrialized countries.
Researchers at Oregon State University have developed an edible coating that triples omega-3 fatty acids in fish, reducing lipid oxidation and preventing microorganism growth. The coating, enriched with fish oil, also maintains moisture levels and prevents color change.
Researchers at Scripps Institution of Oceanography found that high CO2 levels in water lead to abnormally large ear bones in fish, a vital structure for sensing orientation and acceleration. The study suggests potential implications for the survival and behavior of affected fish.
A new study suggests that common fish species, such as the nine-spined stickleback, can compare behavior and make choices based on personal experience, leading to better food supplies. This sophisticated social learning capability, called 'hill-climbing', challenges the idea that big brains are necessary for cumulative culture.
A new study published by Oregon State University researchers found that hatchery fish significantly impair the reproductive fitness of their offspring, even if they survive and reproduce in the wild. This could be hurting efforts to sustain wild salmon runs, scientists said.
A study by Florida State University researcher Chris Stallings reveals a 'sobering' decline of large predatory fishes in the Caribbean, mainly caused by overfishing. The research documents patterns across a greater geographic scale than previous studies, highlighting the impact on marine food webs and coral reefs.
Removing non-native trout from mountain lakes reverses their impact on aquatic insect populations. Aquatic insect abundance increases quickly after trout removal, but suspension of stocking alone is ineffective in restoring insect numbers.
A new study has found that large size and fast bite were the main reasons for the extinction of certain fish 65 million years ago. Today, these same features characterize large predatory fishes that are in decline and at risk of extinction themselves.
A new study suggests that over-dramatized fish health benefits put pressure on wild fish stocks, threatening food security in developing nations. The research highlights the need for sustainable seafood consumption and warns against 'triaging' food sources without verifying their impact.
A new study by Queen's University finds that oil dispersants used to clean up spills increase toxicity to fish, making them more deadly. The study shows that dispersed oil can be 100-fold more toxic to rainbow trout, impairing fish populations and fisheries economic returns
A new study by Cornell University uses advanced tracking technologies to monitor declining fish populations. The research reveals that mixing of stocks is a major issue in unsustainable fishing practices, highlighting the need for updated management strategies.
Biologist Zeb Hogan sets the record straight about a purported record-breaking 771-pound stingray, saying it was never weighed. The fish, caught in central Thailand, is estimated to weigh between 550-770 pounds and may be the world's largest freshwater fish.
A study of nearly 4,000 teenage boys found that eating fish at least once a week increased combined intelligence scores by six percent, while more frequent consumption increased them by 11 percent. The researchers discovered a clear link between frequent fish consumption and higher cognitive performance.
A Scripps Institution of Oceanography study has provided evidence of a drastic decline in Florida's reef fish, with 'trophy fish' shrinking by nearly two-thirds over the last five decades. The study used archival photographs to analyze the weight and length of large predatory fish caught around coral reefs.
A new study on stickleback fish found that followers play a crucial role in good leadership and that individuals adopt roles based on social feedback. The researchers showed that each member of a pair influences the other's behavior, leading to dynamic leadership emergence.
Farming of fish in ocean cages promotes infection and lowers fitness of wild fish, leading to higher death rates. Sea lice are a major example of disease transfer in ocean fish farming, causing widespread decline of wild fish populations.
Researchers found contaminated offspring with underdeveloped brains, inadequate energy supplies, and dysfunctional livers. The study's findings have implications for human health, as the estuary is a primary water source for California.
A comprehensive study on Puerto Rico's freshwater fish species has been conducted by NC State researchers, identifying key features that support native populations and distinguishing those susceptible to invasion. The study aims to inform conservation efforts and management decisions for the island's fisheries.
Stickleback fish follow a consensus decision-making process to choose their leader, prioritizing size, fatness, and health. As group size increases, accuracy improves, but occasional errors occur due to submission to peers and cascades of incorrect decisions.
A genetic study of an Antarctic 'antifreeze fish' has revealed a small set of genes that dominate the transcriptional process, enabling it to survive in cold, oxygen-rich environments. The study found high expression of proteins responding to environmental stress, such as heat shock proteins and ubiquitins.
A new study published in Nature sheds light on the complex changes that occurred during the transition from aquatic to terrestrial lifestyles, including the evolution of limbs and internal head skeleton. The research reveals that Tiktaalik roseae, a transitional fossil, exhibits features of both fish-like and tetrapod characteristics.
A study published in the American Journal of Clinical Nutrition found that consuming oily fish at least once a week may reduce the risk of age-related macular degeneration (AMD) by 50%. Researchers associated high levels of omega-3 fatty acids with lower AMD risk, particularly those above 300mg per day.
A study published by the American Academy of Neurology found that eating broiled or baked tuna and other fish high in omega-3 fatty acids can help prevent silent brain infarcts, which are associated with dementia and stroke. The risk was lower for those who ate these types of fish regularly.
In a new study, male Atlantic mollies were found to deceive rivals about their top mate choice by feigning disinterest and directing advances toward less-preferred females in the presence of other males. This sophisticated behavior highlights that traits ascribed to humans can also be found in simpler animals.
A study found that fish with temperature-dependent sex determination are more vulnerable to climate change, with increasing temperatures leading to a shift towards males. Small changes in temperature can significantly alter the sex ratio, compromising the viability of some fish populations.
A new study found that lionfish can slash the survival of other reef fishes by 80 percent within a short period. The invasive species disrupts the ecological balance of coral reefs, allowing seaweeds to overwhelm them. This is another major threat to coral reefs, following overfishing and pollution.
A meta-analysis of nine studies found that high omega-3 fatty acid intake from fish consumption reduces the risk of late age-related macular degeneration by 38 percent. Regular fish consumption is also linked to a reduced risk of both early and late AMD.
A new species of catfish, Rhinodoras gallagheri, has been named in honor of Frank Gallagher, a retired Academy of Natural Sciences mailroom supervisor. The Orinoco thicklip catfish was discovered in the Academy's collection and is found in the Orinoco basin in Venezuela and Colombia.
Research suggests that healthy adult haddock can produce more eggs of higher quality, leading to larger and better-conditioned offspring. This finding could significantly impact haddock stocks on Georges Bank.
Atrazine, a widely used weedkiller, disrupts hormonal signaling in human cells, increasing the risk of abnormal birth weight and infertility. Exposure to atrazine has also been shown to 'feminize' zebrafish, with female fish outnumbering males at concentrations comparable to those found in agricultural runoff.
A study by University of California - Santa Cruz researchers found that 90% of California's fall-run Chinook salmon population comes from hatcheries. The findings are troubling given the decline in natural populations, which may force commercial and recreational fishing to close.
A newly found fish in Indonesian waters has sparked excitement among scientists due to its unique appearance and possible connection to an unknown family. The fish, resembling a glass sculpture, can burrow into crevices with its soft and pliable body, and its eyes appear to be directed forward.
Scientists warn that butterflyfish, such as the Chevroned Butterflyfish, are at risk of extinction due to their specialized feeding habits. The coral reefs' decline is threatening these fish's survival as they can only eat one type of coral, leading to a high risk of extinction.
Researchers found that miniscule amounts of synthetic estrogen in municipal wastewater can decimate wild fish populations living downstream, causing feminization and reproductive issues. Removing estrogen through wastewater treatment can reverse the adverse impact on wild fish populations, offering a glimmer of hope for recovery.
Researchers found potentially dangerous levels of mercury and arsenic in Lake Baiyangdian, a source of drinking water for thousands. The study highlights the need to apply US environmental research to China's rapidly industrializing environment.
A ground-breaking study finds that allowing fish numbers to rise leads to higher profits, contradicting the assumption that maximizing fishing profits will lead to stock depletion. The study's results suggest a win-win scenario for fisheries and the global marine environment.
A gene in male cichlid fish produces yellow pigment cells on oval spots, attracting female fish. The fish engage in an exotic oral mating behavior, where males deposit sperm in the females' mouths after she picks up eggs.
A diet high in fish, omega-3 oils, and fruits/vegetables can significantly reduce the risk of dementia. The study found a 60% lower risk for those consuming omega-3 rich oils, while a 30% lower risk was seen for those eating fruits and veggies daily.
Researchers found that extracts of channel catfish caught in polluted waters can activate estrogen receptors in breast cancer cells, leading to cell growth. The study suggests that pharmaceutical estrogens and xeno-estrogenic chemicals are contaminating local waterways.
A study by the University of Pittsburgh found that commercially sold white bass contained higher levels of mercury, arsenic, and selenium than those caught near former industrial areas. The pollutants were linked to coal-burning pollution through air emissions and water pollution.
Researchers at the University of Pittsburgh Graduate School of Public Health found higher-than-acceptable levels of mercury and selenium in channel catfish from areas near a coal-fired power plant. Ingesting these fish can increase the risk of neurological disorders, birth defects, and developmental problems.
A new study by Oregon State University reveals that rearing steelhead trout in hatcheries causes a dramatic drop in their ability to reproduce in the wild, with reproductive success dropping by up to 40% per generation.
A recent study at the University of Illinois found that improper handling techniques in catch-and-release fishing can increase the likelihood of released fish being caught by predators. The researchers recommend minimizing time spent angling and releasing fish quickly to reduce physiological stress.
A rare albino ratfish with a crystalline layer on its skin was caught off Whidbey Island, marking the first time such a specimen has been seen by both experts and scientists. The fish's unusual appearance is due to a gene mutation that prevents it from producing melanin.
A three-year study published in the Proceedings of the National Academy of Sciences found that an increase in mercury loading resulted in a significant increase in methylmercury production and accumulation in fish. The study suggests that reducing atmospheric mercury emissions can lead to lower mercury levels in fish within a few years.
A groundbreaking Canada-US study proves a direct link between atmospheric mercury emissions and mercury in fish, with implications for global environmental protection. The research suggests that reducing mercury emissions can lead to lower levels of mercury in fish within a decade.
Hypoxia caused by low oxygen levels in coastal waters impairs fish reproduction by disrupting their hormones. Laboratory studies found that hypoxia decreases serotonin levels in the brain, leading to endocrine disruption.