Animals in natural disasters

Animals living in the wild are particularly vulnerable in natural disasters. Earthquakes, hurricanes, volcanic eruptions, tsunamis, and forest fires can have devastating consequences. Many animals die, drowned or buried alive by dirt, ash, lava, or snow; crushed to death in collapsed or burnt burrows; smashed against trees and rocks, or pelted by hailstones. Others sustain major injuries, including cuts and abrasions to the eyes, wings and gills; respiratory and digestive disorders, eroded teeth; malnutrition; and poisoning from contaminated food and water. Strong volcanic eruptions and fires can temporarily change regional weather, cooling or heating the air, changing winds, or causing rain. Volcanoes, storms, and floods can kill marine animals directly, or cause long-term problems by depositing debris and affecting the temperature and salinity of water. All of this contributes to health problems for marine animals, while changing the circulation of water, which further affects nutrient availability and water temperature.1

A disaster is defined in human terms as a catastrophic event that exceeds a community’s capacity to respond without external assistance.2 Although some definitions only include events that affect humans, nonhuman animals are also affected in large numbers and often lack the ability and resources they need to adjust to the aftermath of a disaster. Usually, natural disasters that harm humans also harm nonhuman animals. Even unusual natural events that are mild by human standards can be catastrophic to animals living in the wild.

The factors that influence the survival of a nonhuman animal in a natural disaster include: the specific adaptations her species has, the stage of life she is in, whether or not it is breeding season, whether she is migratory or has other means of escape, and the particular habitat she lives in. Other factors she might be coping with are her physical condition or ability to take care of herself.3 Animals with sharp eyesight, hearing, or other senses are more likely to escape,4 as are birds who can fly away and larger animals who can run quickly. Small animals can drown more easily, have their burrows inundated by floods or heavy rains, or be crushed or burned when they are trapped with no way to escape.

Animals may be displaced, either because they moved to safer places or because they were swept away by high winds or rushing flood waters. If displaced animals are crowded together in a small area, they risk major outbreaks of disease and parasite infestations. Malnutrition and starvation due to limited food supplies also become major risks. The animals might also be affected by exposure to sun, cold, or wind if they do not have adequate shelter.

Earthquakes and tsunamis

According to United States Geological Survey (USGS), each year there are 15-20 major earthquakes worldwide with a magnitude of over 7.0 and over a thousand that measure above 5.0.5 Unlike hurricanes and volcanoes, earthquakes hit without warning.6 In addition to shaking land, they can shake and displace the seabed. Islands and beaches can disappear from subsiding land or double in size because the land surrounding it is uplifted.7 When the ocean floor is displaced, it can create a tsunami, which is a series of high, fast waves that begin quickly, can cross oceans, and can last for days.8 They may be followed by landslides that bury animals alive and destroy their homes9 or floods that can sweep them away.

A 2016 quake near Kaikoura in New Zealand had devastating effects on some of the animals living there. The worst affected were a colony of Hutton’s shearwaters, seabirds who were nesting at the time of the quake. Half of the large breeding colony was buried by falling rocks, and it is estimated that 25% of the 100,000 birds died. The quake altered the shape and elevation of the seabed, dramatically changing the undersea environment that crayfishes, pauas (a kind of sea snail) and other marine animals depend on. Those who survived the quake itself found themselves in an unfamiliar environment, in which they struggled to survive.10 It’s also likely that some seals died during the quake, as a landslide swept over their breeding grounds.11

When tsunamis strike, birds and other small animals can be washed into the water and be unable to get back to dry land. Some may be pushed inland, far from their nests. Birds’ nests that have to be kept warm might be flooded with cold seawater. Sea birds and fishes who live in shallow waters near the shore are buried alive in sand or debris and suffocate. Fishes are washed ashore where they suffocate because they can’t breathe outside of water. Some beaches are washed away, and freshwater habitats can be flooded with saltwater. Food sources are washed away.12

In addition to causing tsunamis, earthquakes can cause fires, which lead to further death, injury, and destroyed homes.

Volcanoes

There are at least 20 volcanoes erupting around the world at any time, not including volcanoes erupting underwater, which are much greater in number.13 Eruptions can last for months or years, spewing abrasive and toxic lava and ash, causing explosions, and heating nearby water that can boil marine animals alive.

Volcanic eruptions on islands can result in all terrestrial and nearby marine animals being killed or displaced. Terrestrial animals on islands fare worse than marine animals because they are more dependent on the land for nesting and foraging.14 Bird with nests in the caldera are unlikely to escape, as are young birds who can’t fly very far. Marine animals can go out to sea, though their nestlings on the shore might all die. If the lava covers the whole island, other animals have nowhere to run, and will be covered by lava or ash. Volcanoes can kill every animal who is trapped on the island, and destroy the habitats of animals who managed to escape, forcing them to relocate.

Hot lava or ash that flows into the water will kill animals in tidepools who can’t escape. Lava and ash also change the acidity and turbidity of the water, forcing many marine animals to relocate. Ash and other debris get stuck in gills and suffocate fishes, and lava can leave tiny, glassy shards that harm fishes as the water passes through their gills.

Volcanoes can be accompanied by earthquakes and landslides, gas emissions and explosions, including underwater hydrogen gas explosions.15 These explosions raise the temperature of the water around them, acidify the water, and deoxygenate it. This can kill fishes or cause them to leave the area, destroying their habitats so they can’t return.16

Even when they are very close to safe shores, animals can get disoriented as they try to escape hot water and they end up boiled alive. The 2018 eruption in Hawaii covered tide pools, and even boiled away the water from Hawaii’s largest freshwater lake, killing the animals who lived there.17

Ash deposited by volcanoes contains toxic chemicals and sharp edges that harm animals in the area for many years after an eruption. The sharp edges of the ash cause eye and skin irritation, and are abrasive to teeth, hooves, and insect wings. Ingestion of the ash causes respiratory problems and gastrointestinal blockages.18 Ashes and gases destroy and contaminate food and water supplies. Juvenile grazing animals in volcanic areas may grow up with severe dental fluorosis, which causes damage to emerging teeth including weak enamel and teeth that are easily broken or lost. The poor condition of their teeth contributes to deteriorating health.19

If ashes reach the atmosphere, they can affect the climate in the surrounding area for months or years. Droplets of sulfuric acid or ash particles can cool the temperature by up to several degrees Celsius by blocking radiation from the sun. This is the more common climate effect, but if the particles are large enough, they can cause warming instead of cooling by blocking the escape of gases from the Earth.20

Storms

The wind, rain, and debris from storms injure and kill animals and cause a lot of damage to their habitats, including destroying shelters and contaminating food and water sources. During Hurricane Dorian in 2019, winds reached 295 km per hour. Strong winds and rain can cause broken limbs, head trauma, as well as breathing problems and infections from getting water in the lungs. Animals are displaced and orphaned. Most of these problems would not be fatal if the animals were able to receive care, but in most cases they do not. A few lucky mammals and birds get care if they are blown into urban areas and are found disoriented on someone’s lawn.

Rotating storms known as supercell thunderstorms can rise 10 miles high and cause hailstorms and tornadoes. A storm in Billings, Montana in 2019 had winds up to 74 miles per hour (hurricane strength), and thousands of birds – one quarter of the bird inhabitants of the area – were killed or injured after they were pelted with jagged hailstones the size of golf balls.21

When a storm passes over land, larger animals often seek higher ground and many birds can sense changes in barometric pressure and try to fly away. Fishes and other sea animals seek deeper water or try to migrate to a safer place. Some animals like rodents, reptiles, spiders, and insects raft on fallen trees in a river or ocean.22

Storm surges and strong winds can create such pressure on the seabed floor that large amounts of sediment and large objects are thrown around.23 The pressure can also rapidly mix the colder water near the bottom of the ocean with warmer shallow waters. This can cause hypothermia in cold-blooded animals who rely on the water temperature to regulate their body temperature. The strong currents produced by the mixing waters can kill many small and slow moving animals who can’t just swim away.24

Many animals swim away during a storm or shortly before when they detect pressure changes, but territorial animals and slow swimmers tend to be caught up in the storm25 and knocked around. Animals who cannot swim away are hit by reduced oxygen levels in the water combined with changes in salinity. These two factors disrupt mineral and fluid balances, causing malnutrition, oxidative stress, and growth problems.26

Fishes and other sea animals may also be swept far away. Sea animals might try to find shelter in waters farther from the storm, but they can still be pushed to shore by strong enough winds. During Hurricane Andrew in 1992, nine million fishes were killed in Lousiana after being washed up on shore, and 182 million fishes were killed in one area of Florida.27 Cold-blooded fishes and marine animals may be especially vulnerable due to large changes in temperature and salinity in the places they end up.28

Strong winds can dislocate birds, bats, tadpoles, fishes, and other small or baby animals.29 Nests and food supplies can also blow away and remaining food supplies may rot, creating shortages of food and home sites and increasing competition among animals for these resources.30 Birds can survive minor storms by hiding in the cavities of trees or clinging more tightly to branches.31 If they remain in their home habitats during severe storm winds, they are at risk of dying when the trees they live in are destroyed. Those who survive may be swept away hundreds of miles from their homes and be unable to find their way back, especially if they get separated from their flock.

Floods

Smaller animals are more vulnerable to drowning or dying in resulting floods and mudslides.32 Burrowing animals may be safe from smaller disturbances, but torrential rains can collapse their burrows or block the entrances, trapping them or leaving them without shelter. Burrow entrances can be blocked by branches, leaves, stones and other debris moved around by water or wind.

Leaves and debris can also harm marine animals, blocking sunlight, reducing oxygen levels as they rot and suffocating fishes by blocking their gills.33

Fires

A single wildfire can kill millions of animals.34 The flames and smoke of forest fires kill most animals in their path, including many burrowing animals who are too near the surface, and animals who live in rivers and streams as the flames pass over. Even if they survive the fires, the aftermath can leave animals with burns, blindness, and respiratory problems that can be fatal or permanently debilitating. Hurricane force winds can carry embers and ash from a fire up to a mile away, which can trigger new fires.35 Strong fires generate so much energy that they change the local weather by modifying wind and temperature. The moisture coming off a fire can generate clouds that cause rain.36

Large mammals and birds are more likely to survive than other animals. Mammals can run for higher ground, where the land is wet, or else move into streams or lakes. Birds fly away if they can. Animals with better vision, hearing, and smell can begin their escapes earlier.

Some animals, like squirrels, porcupines,37 and koalas38 try to get away by climbing trees, which is not a good strategy in a fire. Other animals may try to flee but then panic and return to their dens. Smaller animals can burrow into the ground but if they don’t burrow deeply enough, they will die when their dens heat up like an oven.39 Other small animals seek shelter under rocks or inside logs.40 Small and slow moving animals are less likely to escape, and those who survive may be more at risk of predation and other risks because of the changing landscape.41

Fleeing animals may die due to smoke inhalation, burns, exhaustion, disorientation, or attacks from waiting predators along the escape path.42 Mothers and babies may not be able to leave, and territorial animals may be more reluctant to leave and end up staying where they are until it’s too late to get away.

Animals who live in forests also have to deal with both short and long-term effects of wildfires. One of the most dangerous short-term effects is shock, which can inhibit an animal’s ability to eat, seek shelter, and protect herself from predators or other aggression.

Smoke injury is usually short-lived and often heals naturally within a few days. However, if it is severe enough or prolonged, it can cause greater harm, including lung damage, vision loss, or blindness. Birds are especially at risk of serious respiratory harm because of how much air they take in relative to their size.43 Burnt skin can cause a lot of pain, limit mobility, and may never heal completely. Singed wings and other appendages can also affect animals’ ability to move around and navigate.

Injured and frightened animals are more susceptible to other threats like predation. Animals who camouflage themselves against bark and leaves may be more exposed because there are fewer trees to hide in or among.44

Burnt areas of a forest absorb less water, so flooding and mudslides are more common after a forest fire.45 Rains after a fire can carry ashes far, poisoning animals far away from the burnt area and damaging their food supply. If the fire takes place near a body of water, ash can get into the water, reducing oxygen levels and getting stuck in gills and lungs.

For humans, public and private resources are spent to reduce risks and mitigate harms from collapsing buildings, fires, floods, landslides, and lack of food and water. Most human deaths worldwide from natural disasters come from collapsing buildings.46 Nonhuman animals also lose their homes and parts of their habitats that they need to survive, but they don’t have access to modern technology or disaster planning agencies. Whether or not an animal can cope with a natural disaster and its aftermath has a lot to do with a combination of factors that are mostly beyond their control.

To read about how to help, see Animals helped in fires and natural disasters.

Further readings

Alho, C. J. R. & Silva, J. S. V. (2012) “Effects of severe floods and droughts on wildlife of the Pantanal Wetland (Brazil)—A review”, Animals, 2, pp. 591-610 [accessed on 14 July 2019].

American Geoscience Institute (2017) “Earthquake basics”, americangeosciences.org, 05 August [accessed on 4 September 2019].

Anderson, A. & Anderson, L. (2006) Rescued: Saving animals from disaster, Novato: New World Library.

Animal Ethics (2015) “What happens to wild animals during hurricanes?”, Blog, 24 Nov [accessed on 12 November 2019].

Cherry, M. J.; Warren, R. J. & Connor, L. M. (2017) “Fire‐mediated foraging tradeoffs in white‐tailed deer”, Ecosphere, 8 (4) [accessed on 30 August 2019].

Dale, V. H.; Swanson, F. J.; Crisafulli, C. M. (2005) Ecological Responses to the 1980 eruption of Mount St. Helens, New York: Springer.

Decker, S. M.; Lord, L. K.; Walker, W. L. & Wittum, T. E. (2010) “Emergency and disaster planning at Ohio animal shelters”, Journal of Applied Animal Welfare Science, 13, pp. 66-76.

Federal Emergency Management Agency (2008) “Preparing your pets for emergencies makes sense. Get ready now”, ready.gov [accessed on 28 August 2018].

Heath, S. E.; Beck, A. M.; Kass, P. H. & Glickman, L. T. (2001) “Risk factors for pet evacuation failure after a slow-onset disaster”, Journal of the American Veterinary Medical Association, 218, pp. 1905-1910.

Hunt, M. G.; Bogue, K. & Rohrbaugh, N. (2012) “Pet ownership and evacuation prior to Hurricane Irene”, Animals, 2, pp. 529-539 [accessed on 28 July 2019].

Irvine, L. (2004) “Providing for pets during disasters: An exploratory study”, Quick Response Research Report, 171 [accessed on 21 September 2015].

Irvine, L. (2006a) “Animals in disasters: Issues for animal liberation activism and policy”, Journal for Critical Animal Studies, 4, pp. 2-16 [accessed on 14 November 2014].

Irvine, L. (2006b) “Providing for pets during disasters, part II: Animal response volunteers in Gonzales, Louisiana”, Quick Response Research Report, 187 [accessed on 20 September 2015].

Irvine, L. (2007) “Ready or not: Evacuating an animal shelter during a mock emergency”, Anthrozoös: A Multidisciplinary Journal of the Interactions of People and Animals, 20, pp. 355-364.

Kuppusamy, Sivakumar (2009) “Impact of the tsunami (December, 2004) on the long tailed macaque of Nicobar Islands, India”, Hystrix – Italian Journal of Mammalogy [accessed on 13 September 2019].

Kouadio, I. K.; Aljunid, S.; Kamigaki, T.; Hammad, K. & Oshitani, H. (2014) “Infectious diseases following natural disasters: prevention and control measures”, Expert Review of Anti-infective Therapy, 10, pp. 95-104 [accessed on 16 October 2019].

Simms, A.; Scott, M.; Watson, S.; Leonard, S. (2019) “Attenuated post-fire fauna succession: the effects of surrounding landscape context on post-fire colonisation of fauna”, Wildlife Research, 46, pp. 247-255 [accessed on 13 October 2019].

Nolen, R. S. (2006) “Congress orders disaster planners to account for pets”, JAVMA News, October 15 [accessed on 3 September 2019].

White, S. (2012) “Companion animals, natural disasters and the law: An Australian perspective”, Animals, 2, pp. 380-394 [accessed on 14 May 2019].

Notes

1 Nagaraja, M. P. (2019] “Salinity”, NASA science [accessed on 1 December 2019]. Hays, G. C. (2017) “Ocean currents and marine life”, Current Biology, 27, pp. R470-R473 [accessed on 5 October 2019].

2 Ritchie, H. & Roser, M. (2019) “Natural disasters”, Our World in Data [accessed on 14 June 2019]. California Department of Public Health (2019) “Know and understand natural disasters”, Be Informed [accessed on 29 August 2019].

5 United States Geological Survey (2002) “Earthquake hazards”, usgs.gov [accessed on 31 August 2019].

6 United States Federal Emergency Management Agency (2016) “Earthquake safety at home”, fema.gov [accessed on 31 August 2019].

7 California Institute of Technology Tectonics Observatory (2007) “What happened during the 2004 Sumatra earthquake”, tectonics.caltech.edu [accessed on 29 August 2019].

8 National Tsunami Warning Center (2018) “Tsunami frequently asked questions”, tsunami.gov [accessed on 23 September 2019].

13 Global Volcanism Program (2013) “How many active volcanoes are there?”, Smithsonian Institution [accessed on 19 September 2019].

19 Flueck, W. T.; Smith-Flueck, J. A. M. (2013) “Severe dental fluorosis in juvenile deer linked to a recent volcanic eruption in Patagonia”, Journal of Wildlife Diseases, 49, pp. 355-366. Flueck, W. T. (2011) “Continuing impacts on red deer from a volcanic eruption in 2011”, European Journal of Wildlife Research, 60, pp. 699-702.

20 University Corporation for Atmospheric Research (2004) “How volcanoes influence climate”, scied.ucar.edu [accessed on 19 September 2019]. United States Geological Survey (2019) “Do volcanoes affect weather?”, usgs.gov [accessed on 23 October 2019].

21 Cappucci, M. (2019) “Montana hailstorm slaughters 11,000 birds”, The Washington Post, 21 August [accessed on 13 September 2019].

23 Geigel, L. (2017) “During a hurricane, what happens underwater?”, op. cit.

24 National Oceanic and Atmospheric Observation (2018) “How do hurricanes affect sea life?”, National Ocean Service, 06/25/18 [accessed on 23 September 2019].

25 Geigel, L. (2017) “During a hurricane, what happens underwater?”, op. cit.

29 The Telegraph (2011) “Strange rain: Animals that have fallen from sky”, The Telegraph, 15 December [accessed on 22 August 2019].

30 Indiana Wildlife Disease News (2009) “Starvation and malnutrition in wildlife”, 4 (1), pp. 1-3 [accessed on 22 August 2019].

39 Campbell, M. (2016) “What will the Fort McMurray fires mean for wildlife?”, op. cit.



40 Zielinski, S. (2014) “What do wild animals do in a wildfire?”, op. cit.

41 Esque, T. C.; Schwalbe, C. R.; Defalco, L. A.; Duncan, R. B. & Hughes, T. J. (2003) “Effects of desert wildfires on desert tortoise (Gopherus agassizii) and other small vertebrates,” op. cit.

42 Daly, N. (2019) “What the Amazon fires mean for wild animals”, National Geographic, August 23 [accessed on 13 September 2019]. Zielinski, S. (2014) “What do wild animals do in a wildfire?”, op. cit.

43 Cope, R. B. (2019) “Overview of smoke inhalation”, Merck Manual: Veterinary Manual [accesed on 23 September 2019].