Impacts of “supermoon” events on the physiology of a wild bird

Abstract

The position of the Moon in relation to the Earth and the Sun gives rise to several predictable cycles, and natural changes in nighttime light intensity are known to cause alterations to physiological processes and behaviors in many animals. The limited research undertaken to date on the physiological responses of animals to the lunar illumination has exclusively focused on the synodic lunar cycle (full moon to full moon, or moon phase) but the moon's orbit—its distance from the Earth—may also be relevant. Every month, the moon moves from apogee , its most distant point from Earth—and then to perigee, its closest point to Earth. Here, we studied wild barnacle geese ( Branta leucopsis ) to investigate the influence of multiple interacting lunar cycles on the physiology of diurnally active animals. Our study, which uses biologging technology to continually monitor body temperature and heart rate for an entire annual cycle, asks whether there is evidence for a physiological response to natural cycles in lunar brightness in wild birds, particularly “supermoon” phenomena, where perigee coincides with a full moon. There was a three‐way interaction between lunar phase, lunar distance, and cloud cover as predictors of nighttime mean body temperature, such that body temperature was highest on clear nights when the full moon coincided with perigee moon. Our study is the first to report the physiological responses of wild birds to “supermoon” events; the wild geese responded to the combination of two independent lunar cycles, by significantly increasing their body temperature at night. That wild birds respond to natural fluctuations in nighttime ambient light levels support the documented responses of many species to anthropogenic sources of artificial light, that birds seem unable to override. As most biological systems are arguably organized foremost by light, this suggests that any interactions between lunar cycles and local weather conditions could have significant impacts on the energy budgets of birds.

Seasonal variation in sleep homeostasis in migratory geese: a rebound of NREM sleep following sleep deprivation in summer but not in winter

“…Indeed, the daily amount of NREM sleep was 2.0 h lower during full moon than during new moon. This finding appears to be in agreement with earlier reports showing that barnacle geese are more active and have an increased heart rate and body temperature during nights with a full moon [ 52 ]. Also, our own recent work in starlings showed that this songbird on average sleeps 2 h less on nights with a full moon [ 16 ].…”

Supermoon Drives Beach Morphological Changes in the Swash Zone

“…The full moon on 8 April 2020, which is an example of a recent supermoon, was 14% larger in apparent diameter than the smallest full moon, or “micro–full moon,” on 31 October 2020 (NAOJ, 2020). Scientists suggest that the supermoon can also affect some natural phenomena (e.g., Portugal et al, 2019). It has greater gravitational force than the normal full or new moon and produces a larger tidal range, in particular the high tide known as the “king tide” (Flick, 2016; NOAA, 2019).…”

Mechanics Of Flight Feathers: Effects Of Captivity?

“…On the completion of moult, the 95 newly grown 9 th primary feather was removed. Flight feathers from wild Barnacle Geese were collected during wing moult, at Ny-Ålesund, Spitsbergen (78°55′N 11°56′E78.917°N 11.933°E,)(see Portugal et al 2011c;Portugal et al, 2019a;Portugal et al,. 2019b).…”