19/10/2024
AUTUMN & DOGS: THE FASCINATING WORLD OF PHOTOPERIODS
Autumn can be a lovely time, and with it comes a noticeable change in the environment. The air cools, leaves slowly turn shades of orange and gold, and daylight hours begin to shorten. While we might embrace the cosy jumpers and pumpkin-spiced treats, dogs experience a host of physiological and behavioural changes during this transition, many of which are considered ‘biologically conserved’ in evolutionary terms.
Just as in spring, the neuroendocrine system of animals adjusts in response to the changing season, particularly in relation to sunlight exposure, also referred to as a photoperiod. During autumn, the shorter days begin to trigger an increase in melatonin production, which affects various biological rhythms in many species, including dogs. This increased melatonin not only influences sleep cycles but also prepares animals for the winter months ahead, often inducing behaviours aimed at conserving energy.
The dogs’ shedding patterns might intensify, as shedding of summer coats is essential for the growth of thicker winter fur that offers protection against the upcoming cold. Alongside changes in physical appearance, dogs’ behaviours also shift as autumn arrives. The drop in temperature can be invigorating for many dogs (especially longer-coated or thick-coated breeds), leading to bursts of energy and increased activity levels. Some dogs may appear more alert or eager to engage in outdoor play, taking advantage of the milder temperatures before winter sets in. Conversely, dogs with health conditions such as arthritis and allergies might experience flare-ups.
Interestingly, autumn also brings a change in the activity of some prey animals. The reduced movement of rodents and other small mammals may lessen the intensity of hunting or prey drive that some dogs displayed in spring. However, depending on the region, autumn might bring migration patterns or increased activity in certain prey species, which could reignite that drive in more prey-oriented breeds. Early in the autumn, squirrel activity is heightened as they prepare to collect nuts in anticipation of mating season and winter, taking more risks. This can be a heady experience for many dogs, who might show over-excitement in areas where they remember spotting them. In the UK, red deer undergo rutting season between September and November, which again can influence how a dog might behave, depending on the location.
For dogs, autumn is also a season rich with new smells. Decomposing leaves, damp soil, fungal spores, and the heightened activity of foraging animals preparing to store fat reserves can create an olfactory feast. Similar to the distractions of spring, dogs may become deeply immersed in exploring these new scents, which could manifest in longer sniffing sessions during walks or more pronounced foraging behaviours. For dogs that are especially scent-driven, this can be a stimulating time, and dog guardians might notice their pets spending extra time investigating their environment. However, this also brings an increased risk of gut upset and ticks for many dogs. With more rainfall, many areas can become hazardous with waterlogging and mud, and if dogs have previously run around in familiar places, they might not be aware of the changing ground conditions. A good way to prepare for this is to begin some simple proprioception exercises, which can be easily set up at home, as this will improve their body confidence and spatial awareness, thus reducing the risk of slips.
One significant behavioural change often observed in autumn is the alteration of sleep patterns. Just as humans tend to sleep longer as the days shorten, dogs, too, may experience an increase in restfulness during the autumn months. The increase in melatonin production, coupled with fewer daylight hours, can lead to dogs seeking out naps more frequently. This change in energy levels can also reflect an evolutionary instinct to conserve energy for the coming winter.
Dog guardians may also notice that their pets become more food-driven during the autumn months. This is a common behaviour rooted in an instinct to build up energy reserves before the scarcity of winter. While modern dogs may not need to prepare for food shortages in the same way their wild ancestors did, the drive to eat more in autumn remains. We should be mindful of this change in appetite and respond accordingly. If weight is not an issue, a minor increase in food intake could be beneficial, especially for dogs who have a history of starvation or who resource guard. More recently, there have been some studies of the relationship between photoperiods and leptin, a crucial hormone that inhibits hunger and regulates energy balance so that the body doesn’t trigger a hunger response when it doesn’t need energy. As leptin follows a diurnal pattern, it is likely to have a relationship with photoperiods. It is always interesting to observe voluntary feeding patterns in various dog breeds, as some seem to prefer eating during the day while others prefer to eat at or after dusk.
In some dogs that show compulsive behaviours like light or shadow chasing, the lessening of light hours and consistently dull skies might prove beneficial. However, it’s important to note that the behaviour is likely to show spontaneous recovery on days that are suddenly light-filled. Additionally, indoor environments may have more artificial lights on due to the loss of daylight, which could also be significant.
Rescue dogs from differing climates and time zones might show varied responses to autumn. Some may struggle to adjust to weather differences, and exposure to darkness might trigger more fear responses.
We also now have more research supporting a link between the gut microbiome and photoperiods. A truly fascinating area of scientific exploration. A recent study in Siberian hamsters showed that there were gut responses to the photoperiod that influenced aggression. ( link in comments) The study revealed differentially affected bacterial diversity and the relative abundance of bacteria in the male and female gut, suggesting that the gut microbiome may play a role in sex-specific seasonal changes. With further research, targeted therapies look promising for many species.
As with spring, autumn’s changes can sometimes lead to frustration for both dogs and their humans . Recognising and understanding the evolutionary biology behind these seasonal shifts can help better navigate dogs’ behaviours. Engaging in targeted enrichment and proprioception, offering opportunities for scent work, and adjusting daily routines to accommodate changing energy levels and increased appetite can all help make the transition into autumn a supportive and enriching experience.
Boo Blackhurst, CDBC
