Knowledge Tree
full-moon
Facts (79)
Sources
Lunar effect - Wikipedia en.wikipedia.org 29 facts
measurementThe increase in births on full moon days is +0.4%.
claimCorals at the Great Barrier Reef release their eggs and sperm simultaneously after the full moon between October and December.
referenceD. Redelmeier and E. Shafir published a population-based double control study in 2017 in the BMJ titled 'The full moon and motorcycle related mortality', which investigates the link between the full moon and motorcycle-related deaths.
claimA 2021 study by researchers from the University of Washington, Yale University, and the National University of Quilmes showed that during the days preceding a full moon, people went to bed later and slept for shorter periods, with differences of up to 90 minutes, even in locations with full access to electric light.
claimThe bristle worm Platynereis dumerilii spawns a few days after a full moon.
formulaTides are highest when the Sun, Earth, and Moon are aligned, which occurs at the new moon or full moon.
claimA spokesman for the Royal College of Surgeons stated they would 'laugh their heads off' at the suggestion that surgeons cannot operate during a full moon.
claimA 2000 retrospective study in the United Kingdom reported that animal bites to humans increased significantly during the full moon between 1997 and 1999.
claimThe bristle worm Platynereis dumerilii spawns a few days after a full moon and is used as a model organism for studying cryptochromes and photoreduction in proteins.
claimSeveral studies have argued that stock market average returns are higher during the half of the month closest to the new moon compared to the half closest to the full moon, with authors suggesting potential lunar influences on mood.
referenceEva Maria Roman, German Soriano, Mercedes Fuentes, Maria Luz Galvez, and Clotilde Fernandez published 'The influence of the full moon on the number of admissions related to gastrointestinal bleeding' in 2004, investigating the relationship between the full moon and hospital admissions for gastrointestinal bleeding.
claimThe 2000 retrospective study in the United Kingdom concluded that animals have an increased inclination to bite humans during a full moon period.
claimThe validity of the 2013 University of Basel study on the full moon and sleep quality is limited by a small sample size (n=33) and inappropriate controls for age and sex.
measurementA study of 13,029 motorcyclist fatalities in nighttime crashes found a 5.3% increase in fatalities on nights with a full moon compared to other nights, which the authors speculate may be due to visual distractions caused by the moon.
claimThe belief that there is a large surplus of births on full moon days is incorrect.
claimA 2013 study by Christian Cajochen and collaborators at the University of Basel suggested a correlation between the full Moon and human sleep quality.
claimA research team in Barcelona, Spain, reported a weak correlation between lunar phases and hospital admissions for gastrointestinal bleeding when comparing full moon days to all other days combined.
claimPolice departments in Ohio and Kentucky have attributed temporary increases in crime rates to the full moon.
claimBarau's petrels time their mating season with the full moon.
claimCalifornia grunion fish spawn on four consecutive nights, beginning on the nights of the full and new moons, when tides are highest.
measurementA 2016 study of 5,812 children found a five-minute decrease in sleep duration near the full moon.
claimThe statistical significance of the Barcelona team's findings regarding lunar phases and hospital admissions disappears when comparing full moon days to specific other days in the lunar cycle (days 9, 12, 13, or 27).
claimSerious doubts have been raised regarding the claim that a species of Ephedra synchronizes its pollination peak to the full moon in July.
referenceFrédéric Chambat, Anne-Laure Fougères, and Alexandre Elyildirim published 'Slightly more births at full moon' in 2021, reporting a finding of slightly higher birth rates during the full moon.
claimAcropora coral synchronize the release of sperm and eggs to one or two days a year, occurring after sundown during a full moon.
measurementA 2015 study of 795 children found a three-minute increase in sleep duration near the full moon.
measurementA 2021 analysis of 38.7 million births in France over 50 years found a small (+0.4%) but statistically significant surplus of births on the full moon day and the following day, with a p-value of 1.5 x 10-5.
referenceA 2000 retrospective observational analysis published in the BMJ by Yonezawa et al. investigated whether animals bite more frequently during a full moon.
referenceScott O. Lilienfeld and Hal Arkowitz published an article in 2009 titled 'Lunacy and the Full Moon' in the journal Scientific American Mind, which discusses the relationship between the full moon and human behavior.
How the Full Moon Affects the Behavior of Animals ruhighlander.org May 2, 2024 13 facts
claimScientists suggest that the increased risk of medical emergencies for pets during a full moon may result from pets spending more time outside at night when the moon is brighter.
claimOysters narrow their shells as a full moon approaches and widen their shells as the full moon diminishes.
claimThe full moon can lead to less deep sleep and a delay in entering REM sleep in humans.
claimThe full moon has a significant effect on a variety of animals, many of which inhabit the ocean.
claimThe full moon causes enhanced levels of activity in animals due to the bright reflection and extended periods of light.
claimCoral reefs synchronize the release of egg and sperm in response to the proximity of a full moon, resulting in the largest spawning event on Earth.
claimSome studies have shown a slight change in cardiovascular conditions in humans during a full moon.
claimAccording to The Weather Network, various animals, including oysters, coral reefs, and sharks, exhibit behavioral changes during a full moon.
claimThere is no absolute scientific proof supporting a change in the mental stability of healthy individuals during a full moon, despite anecdotal reports of mood swings and mental imbalance.
quoteThough a Full Moon only occurs during the exact moment when Earth, Moon, and Sun form a perfect alignment, to our eyes, the Moon seems Full for around three days.
claimA full moon occurs when the most sunlight reflects off the Moon toward Earth, creating an intense glare that makes other celestial objects like stars and planets more difficult to observe.
quotePeople anecdotally report that the full moon affects their mood, but the existing research does not support this claim. An older 1985 meta-analysis found no connection between phases of the moon and mental health admissions to hospitals.
measurementA 10-year study conducted at the Colorado State University’s College of Veterinary Medicine and Biomedical Sciences' Medical Center, involving nearly 12,000 cases of dogs and cats, found that the risk of medical emergencies is 28% greater for dogs and 23% greater for cats in the days surrounding a full moon.
Moonlight shapes how some animals move, grow and even sing sciencenews.org Jul 8, 2019 9 facts
claimShima observed that some young sixbar wrasses delay their return to coral reefs by several days to avoid arriving during a full moon.
measurementMale white-browed sparrow weavers start singing about 10 minutes earlier on average during a full moon compared to a new moon, according to a 2014 study by Jenny York and colleagues published in Biology Letters.
measurementJeff Shima and Stephen Swearer estimated in the journal Ecology that the growth advantage of a full moon relative to a new moon for common triplefin larvae is similar to the effect of a 1-degree Celsius increase in water temperature.
claimFoster and colleagues evaluated the strength of the polarization signal in the night sky over dung beetle territory and found that the proportion of polarized light during a nearly full moon is similar to that of polarized sunlight during the day, which many daytime insects use to navigate.
claimYoung sixbar wrasses appear to stay at sea several days longer than normal to avoid arriving at coral reefs during a full moon, likely because darkness provides cover from sight-hunting predators.
measurementThe growth advantage of a full moon for common triplefin larvae is comparable to the effect of a 1-degree Celsius increase in water temperature.
measurementFor approximately six days around a full moon, zooplankton hide at depths of up to 50 meters.
measurementIn a study of over 1,000 young sixbar wrasses (Thalassoma hardwicke) arriving at coral reefs in French Polynesia over 11 months, more than 50 percent arrived during the darkness of a new moon, while only 15 percent arrived during a full moon.
claimThe extra light from the full moon, rather than other aspects of the lunar phase, causes male white-browed sparrow weavers to start singing earlier, as they maintain a normal schedule when the full moon is below the horizon at dawn.
Lunar Cycles And the Underwater World dipndive.com 5 facts
claimSharks tend to stay in deep water during the full moon and move to shallow waters during the new moon.
measurementA lunar cycle, equivalent to the astronomical synodic month, takes place every 29.5 days, during which the moon completes its waxing and waning phases from new moon to full moon and back to new moon.
measurementThe greatest number of spawning horseshoe crabs occurs during the full moon, while the least active spawning period is during the new moon.
claimStreaked shearwaters, a pelagic seabird species in eastern and Southeast Asia, fly for longer periods and land on water more frequently during full moon nights compared to new moon nights.
claimIncreased moonlight intensity during the full moon increases visibility near the surface, causing some fish species to settle to avoid predation while larger fish species remain mobile to hunt prey.
To the Moon and Back: How Lunar Cycles Shape Earth's Wildlife nathab.com May 28, 2025 4 facts
claimThe date of Easter is determined by the lunar cycle, occurring on the first Sunday following the first full moon after the spring equinox.
measurementA complete lunar cycle, defined as the time from one full moon to the next, lasts 29.5 days.
claimA full moon occurs when Earth is positioned between the sun and the moon, revealing the moon's fully illuminated face.
claimDuring new and full moons, the alignment of the sun, Earth, and the moon intensifies tidal forces, resulting in 'spring tides,' which are characterized by higher high tides and lower low tides.
The moon has power over animals - Science News Explores snexplores.org Nov 7, 2019 3 facts
claimSixbar wrasses appear to delay their arrival at coral reefs by several days to avoid settling during a full moon, likely because darkness provides protection from sight-hunting predators.
measurementZooplankton migrate to depths of approximately 50 meters (165 feet) for about six days around a full moon.
measurementThe proportion of polarized light in the night sky during a nearly full moon is similar to the proportion of polarized sunlight during the day, which insects like honeybees use for navigation.
How does the Moon affect life on Earth? | Natural History Museum nhm.ac.uk 3 facts
claimThe mass spawning of corals on the Great Barrier Reef occurs between October and December, specifically triggered to happen right after a full Moon.
quote“The corals time their spawning according to several factors, including temperature, salinity and availability of food. But it always occurs between October and December and right after a full Moon.”
claimBarau’s petrels (Pterodroma baraui) synchronize their arrival at breeding grounds to coincide with the full Moon, suggesting they use both the Moon and day length to coordinate migration.
3 ways the moon affects wildlife discoverwildlife.com 2 facts
procedureThe reproductive cycle of the marine annelid worm Platynereis dumerilii proceeds as follows: (1) sex cells mature under the full moon, (2) exactly 14 days later under the new moon and four hours after sunset, the worms float to the surface, (3) the worms synchronously release eggs and sperm, and (4) the worms die after spawning.
claimBarau’s petrels arrive at their breeding grounds on the island of Réunion at the full moon, suggesting they use the moon to synchronize their migrations.
Wildlife Wednesdays: Odd Lunar Effects on Sea Animals weatherology.com 2 facts
claimSpeckled sea lice exhibit a monthly activity cycle where they are more active during full and new moons, which correspond with stronger currents, and less active during quarter moon phases and weekly neap tides.
claimArctic zooplankton take cover during full moon phases because the lunar light allows predators to hunt them, causing the zooplankton to time their feeding to the rising and setting of the Moon.
How Lunar Cycles Guide the Spawning of Sea Creatures smithsonianmag.com Mar 8, 2023 2 facts
accountDuring its reproductive season, the marine bristle worm Platynereis dumerilii spawns a few days after the full moon by rising en masse to the water surface at night, engaging in a nuptial dance, releasing gametes, and subsequently bursting and dying.
claimMarine bristleworms use a six-hour window of moonlight exposure during a full moon to synchronize their spawning with monthly lunar cycles.
The Lunar Clock Beneath the Waves: How Marine Life Runs on ... bioneers.org Jul 16, 2025 2 facts
How Does the Moon Affect Our Ocean? oceanconservancy.org Feb 6, 2020 1 fact
perspectiveIf humans are influenced by the gravitational pull of the full moon, tidal force dictates that humans should be equally impacted by the new moon.
An Overview of Monthly Rhythms and Clocks - Frontiers frontiersin.org 1 fact
claimChaput, Weippert, LeBlanc, Hjorth, Michaelsen, Katzmarzyk, and others studied the association between the full moon and sleep and activity behaviors in an international sample of children in a 2016 article published in Frontiers in Pediatrics.
The lunar cycle: effects on human and animal behavior and physiology pubmed.ncbi.nlm.nih.gov 1 fact
claimIn birds, daily variations in melatonin and corticosterone disappear during full-moon days.
The moon's cycles influence wildlife behavior - Facebook facebook.com Dec 28, 2024 1 fact
claimCertain owl species increase their activity levels during the full moon, specifically regarding mating calls and the display of feathers to potential mates.
Why oysters close on the full moon—and more odd lunar effects on ... nationalgeographic.com Apr 17, 2019 1 fact
claimDuring full or new moons, the moon aligns with Earth and the sun, exerting a strong gravitational pull that causes pronounced tides, according to marine biologist David Wilcockson.