Physical and biological risks present an array of challenges for wildlife and other natural resource professionals, and members of the public in their pursuit of outdoor recreation. Wildlife professionals, in particular, are often faced with natural hazards with great frequency as a routine part of their job requirements and duties.
Recently, I was surprised by a colleague’s choice of attire for a rescued venomous snake reintroduction effort in India. This individual wore flat, open-toed shoes to release some of the world’s deadliest snakes back into a wildlife preserve. Safer measures were certainly in order for such dangerous work.
I also have worked as a relief keeper and general curator at zoos and sanctuaries and in the field with a variety of vertebrate taxa and have first-hand knowledge of the kinds of injuries that even seemingly benign species can inflict on humans. As one saying goes, “If it has a mouth, it can bite.”
What do wildlife professionals need to know to ensure their own health and safety when working outdoors? What hazards does the general public encounter when they interact with wildlife and nature?
To help answer these questions, I again turned to wildlife expert Dr. Michael Hutchins who has traveled to field sites in over 30 countries to pursue his passion for wildlife management and conservation. Michael also began handling and restraining captive and free-ranging wildlife while studying Rocky Mountain goats in Olympic National Park, WA and working at the Bronx Zoo, one of the most diverse mammal collections in the world. Early in his zoo career, he was responsible for the physical restraint of a wide variety of animals during veterinary rounds. Michael has participated in several interviews for Nat Geo News.
Jordan: Can you specifically address encounters with poisonous and venomous species? Can you discuss how potentially dangerous wildlife is viewed by those working outdoors in the wildlife profession? Please include both terrestrial and aquatic species, including invertebrates and fish.
Michael: First let me address an issue that is a pet peeve of many biologists, and that is the difference between the terms “venomous” and “poisonous.” Many lay people use the terms interchangeably, when, if fact, they are very different. A poison is typically ingested, whereas venom is injected or actively introduced into the victim’s body. An example of the former is the cane toad (Bufo marinus)—potential predators of the toad are poisoned by toxic secretions produced by glands on the skin when they try to ingest the animal. An example of the latter is the king cobra (Ophiophagus hannah), a large predatory snake that literally injects venom through its syringe-like fangs that are connected to venom glands. Some venomous species, such as rear-fanged snakes and gila monsters (Heloderma suspectum, one of the world’s few venomous lizards) must chew in order to introduce the venom, since they have no efficient way of injecting it. In addition, some poisons can be introduced through means other than ingestion, as for example, when someone with a cut on their hand picks up a poison dart frog, and the poison enters the blood stream through a skin abrasion.
Having spent many years traveling and interacting with wildlife and nature in many parts of the world, I have had numerous encounters with poisonous and venomous wildlife. A few of the things I remember most vividly was nearly stepping on a Fer-de-lance (Bothrops asper , a cryptically –colored highly venomous snake) in Corcavado National Park, Costa Rica; walking barefoot on a tide flat in Shark Bay, Western Australia and nearly stepping on a small stonefish (family Synanceiidae); waking up one morning and finding a foot-long centipede (Scolopendra gigantean) under my sleeping bag in the Galapagos Islands, Ecuador; hiking through an arid landscape in the Potholes of Eastern Washington that was filled with Pacific rattlesnakes (Crotalus oreganus); and being within a few feet of a deadly tiger snake (Notechis scutatus) in the picnic ground of a national park on Kangaroo Island, South Australia. I’ve also happened upon and observed many poisonous and venomous species over the years, including poison dart frogs (family Dendrobatidae) , wasps (order Hymenoptera), and eyelash vipers (Bothriechis schlegelii) in Costa Rica, killer bees (Apis spp.) in Brazil, cane toads, blue-ringed octopus (Hapalochlaena spp.), fire coral ((family Milleporidae) and cone shells (family Conidae) in Australia, and black widow spiders (Latrodectus spp.) in the American Southwest.
Yet, at no time was I ever afraid of these creatures. Why? Because, when it comes to dangerous wildlife, knowledge is power (Nichol, J. 1989. Bites and Stings: The World of Venomous Animals. New York: Facts on File). For example, when hiking through areas inhabited by venomous snakes, it is prudent to keep one’s eyes fixed on the ground and be aware of where you are stepping at all times. In addition, never put your hands or feet somewhere where you can’t see them (http://wildlifetourism.org.au/snake-danger-in-australia-usually-not-if-youre-careful/). Many people are bitten reaching up for a handhold while climbing up steep, rocky terrain or stepping off fallen logs when they can’t see the other side. In the case of the Fer-de-lance mentioned above, I escaped injury by being hyper-aware. I was walking behind my guide looking up to see if we could locate and identify some parrots that were vocalizing loudly in the canopy just above us. My guide, who was wearing flip-flops and shorts at the time (not a good idea in snake country), was not paying attention and stepped on the snake. There is some truth to the story that the first one in line aggravates the snake and the second one gets bitten. Fortunately, I looked down before moving forward and saw the snake writhing on the ground in front of me. I jumped backwards rapidly, as I was able to immediately identify the species. Lesson number two is to be able to identify the venomous and non-venomous creatures in the areas you are traveling. In actuality, I was in little danger at the time because the snake was in the process of feeding and had a large lizard halfway down its throat. The animal was rapidly moving its head back and forth in an effort to dislodge its meal so that it could defend itself. In fact, Fer-de-lance are “sit and wait” predators that lie motionless next to trees or on frequently-used animal trails waiting for a meal to happen by. That makes them even more dangerous as their cryptic coloration and behavior makes them extremely difficult to see in leaf litter.
Lesson number three: Know something about the behavior of poisonous or venomous animals in the areas you are working or traveling. Knowing the kinds of habitats and conditions one might usually encounter a venomous or poisonous species is an important piece of information. A few years ago, I was hunting fossils in the Wyoming badlands. I left my colleagues behind and began walking down a gully where I was finding numerous pieces of petrified wood. I walked by sagebrush, heard something move inside and instinctively gave the plant a wide berth as I passed by. One of my colleagues was walking some distance behind me along the same path and when he got to the plant—sure enough– there came the distinctive rattle of a large prairie rattlesnake (Crotalus viridis). My friend was irritated with me, asking me why I didn’t warn him that a snake was under that bush. He saw me avoid the plant, so he was sure I must have detected the animal. I told him, no, I hadn’t seen or heard the snake rattle, but that I knew where snakes hang out in the middle of the day and, having heard a sound, instinctively took the wider route. He was quite startled by the snake and I’m still not sure he’s ever forgiven me. My avoidance of the bush in question was based on the fact that snakes, being exothermic, are not active when it is cold. When their body temperatures rise, they can begin to move about, but in the heat of the mid-day, they seek shade in order to regulate their temperature. I actually like rattlesnakes, because unlike sit and wait predators, they warn you with the distinctive rattle at the tip of their tails. For this characteristic they have earned the moniker “gentleman snake.”
Another thing about venomous snakes: they don’t always inject toxins when they bite. Producing the toxin is energetically expensive, and the reptiles are therefore conservative in its use. Some bites are so-called “dry bites.” Archie Carr, Sr. wrote a wonderful essay called “Bitten by a fer-de-lance”, which was published in Natural History Magazine and reprinted in a book in 1975 (Ternes, A. (ed.) 1975. Ants, Indians and Little Dinosaurs: A Celebration of Man and Nature for the 75th Anniversary of Natural History Magazine. New York: Scribner’s). Carr, who is famous for his field studies of sea turtles, was bitten walking down a trail near the small, coastal village at Tortuguero, Costa Rica, a place I have been at least twice. Carr uses the story as a tool to educate readers about the composition and power of snake venom, how antivenins work, and the incidence of dry bites—bites, which don’t lead to envenomation. As it turns out, he was allergic to the antivenin and the essay recounts his struggle with the decision whether or not to accept treatment. Fortunately, the bite was dry and he survived the ordeal.
This is not usually a problem in the case of wildlife professionals who value the ecological role that poisonous or venomous animals play in their respective environments; however, the public often views such animals with fear and trepidation. Rather than calling in animal control experts to remove venomous snakes, some people try to dispatch the animals themselves. Not a good idea. Not surprisingly, when threatened with a shovel or stick, the animals try to defend themselves, and this is when people often get bitten. When dangerous animals are involved, it is best to call on experts to dispatch them and preferably to live capture and relocate them to suitable habitat away from human habitation. Unfortunately, ophiophobia or the fear of snakes appears to have both a learned and instinctive component in humans, thus making it difficult to change people’s attitudes about them (Burghardt, G. Murphy, J.B., Chaizar, D, and Hutchins, M. 2009. Combating ophiophobia: Origins, treatment, education and conservation tools. Pp. 262-280 in Mullin, S.J., and Seigal, R.A. (eds.) Snakes: Ecology and Conservation. Ithaca, NY: Cornell University Press). This, in turn, can make it more difficult to offer a compelling case for their conservation.
Modern technology can ensure safety from venomous snakes for a price. Outdoor suppliers sell “snake boots”, which are reportedly impervious to the bites of any venomous snake. However, being knee-high and heavy, they’ve never looked particularly comfortable to me, especially in warmer weather. Snake bite kits, even those with antivenin, are also available for sale. If by any chance, you are bitten by a venomous snake, medical experts now argue against cutting the wound and trying to extract the venom. Instead, they advise, washing the bite wound with soap and water, removing any tight clothing or jewelry from around the site, restricting movement as much as possible, and transporting the victim to a hospital immediately, so that antivenin can be administered. In order to ensure that the proper antivenin is administered, it is important to identify the species of snake involved.
Bees and wasps pose a constant danger to those who spend time outdoors. A single bee or wasp sting is no big deal, except of course to those who are allergic; but, when individuals are stung numerous times by large swarms of these social insects, the result can be fatal. I climbed a tall communications tower at Iguacu National park in Brazil in 1992 with three colleagues. The Brazilian biologist we were with wanted us to get a good look at the tropical forest from high above the canopy. About half- way up he suddenly said, “be quiet and move slowly—there is a killer bee nest on this platform.” Fortunately for us, no killer bees saw fit to attack us, but these invasive insects, hybrids between the honey bee and an African variety, are well known for their aggressive disposition and are easily aroused to attack.
Many people are also afraid of spiders, all of which are venomous to one degree or another. Most spiders are relatively harmless, but there are exceptions, such as Australia’s endemic funnel-webbed spider (Atrax robustus), a highly aggressive and venomous species. Its bite can kill a child. Unfortunately, the spider’s primary habitat is Sydney, which often puts the arachnid in close proximity to humans.
In the U.S., the two most dangerous spiders we have are the black widow, with its distinctive red-hour-glass marking, and brown recluse (Loxosceles reclusa), with its distinctive violin or fiddle marking. The brown recluse is rarely aggressive, and bites from this species are uncommon. However, this spider produces a, potentially, deadly hemotoxic venom. Reactions to bites are highly variable and some people show no symptoms at all. In some cases, however, bites may lead to tissue necrosis. Rarely, a bite may affect the entire body; systemic symptoms most commonly experienced include nausea, vomiting, fever, rashes, and muscle and joint pain. Deaths are extremely rare, with most fatalities occurring in children under the age of seven or older individuals with weak immune systems. Due to the presence of a neurotoxin in their venom, black widow bites are also potentially dangerous. Besides the intense pain, this spider’s bite can cause muscles to cramp and become rigid, as well as causing nausea, respiratory problems, irregular heartbeat, and paralysis. There is now an antivenin to counteract the venom’s effects and that is the recommended treatment. In the 1800’s, many unfortunate men were bitten by black widows while sitting in outhouses, accounting for nearly 80% of all recorded bites. Quite a few people died in those days, mainly because no antivenin was available.
Scorpions (order Scorpiones) are another potential danger in some regions of the world, including the southwestern United States. Found on all continents except Antarctica, these predatory arthropods possess a stinger on the tip of their segmented tails, which is connected to a venom gland. Despite their fearsome reputation, only around 25 out of almost 1500 species have venom capable of killing a human. When it comes to scorpions, the general rule is the smaller the species, the more dangerous. The bark scorpion (Centruroides sculpturatus), an inhabitant of the Sonoran Desert, is considered the most venomous scorpion in North America. A sting can cause severe pain in adult humans, typically lasting between 24 to 72 hours. Scorpions are nocturnal and typically seek shelter during the heat of the day in underground holes or under rocks. When in scorpion habitat, it is a generally good idea to check your shoes and clothing in the morning before putting them on to make sure nothing is hiding in them. Fatalities from scorpion envenomation in the U.S. are generally limited to young children and to older adults with compromised immune systems. Extreme reaction to the venom is characterized by numbness, frothing at the mouth, paralysis, and seizure-like symptoms that can interfere with breathing. A Mexican-produced antivenin received FDA approval in 2011 and is now available for use. My closest encounter with a scorpion was in Drake Bay, Costa Rica. We were just settling into our cabin for the night, when my wife pointed to something on the curtains and said, “what is that?” It was a four-inch long scorpion. Not wanting it to spend the night with us, I carefully removed it from the curtain with a magazine and released it outside.
When diving, snorkeling, or walking on the beach in many tropical and subtropical area of the world, one must be aware of venomous marine animals. There are many species of venomous fish and invertebrates. As mentioned previously, I nearly stepped on a juvenile stonefish while walking barefoot on a tidal flat in Shark Bay, Western Australia. This fish has a sharp spine on its dorsal fin, which is attached to a venom gland. The fin is erected when the fish is threatened. Stings from these fish are extremely painful. Scorpion fish (family Scorpaenidae) are another venomous species from the tropical Indo-Pacific. There are also sea snakes (family Hydrophiinae)—relatives of the cobra—who live most of their lives in the ocean, only coming on land to lay their eggs. These animals possess a potent neurotoxin. Fortunately, they are seldom aggressive, except during the mating season, and have small mouths and fangs. Consequently, bites are very rare. I have also seen the venomous blue-ringed octopus, which is a beautiful animal, with vibrant blue colors, but which has a dangerous bite and should never be handled.
While beachcombing in the Indo-Pacific, one is often attracted to beautiful marine shells, which can be found in abundance. However, one of the most attractive of these species is potentially dangerous—the cone snail, of which there are many varieties. All Conus species are venomous and capable of “stinging” humans with their harpoon-like modified radula tooth, which is connected to a venom gland. The tooth is barbed and can be extended some distance out from the mouth of the snail. Live specimens must be handled with great care or preferably not at all. The sting of small cones is similar to a bee sting; however, the sting of some of the larger species can be serious, occasionally even leading to death. Another potential threat while diving or snorkeling is the ubiquitous fire coral. Fire corals have a bright yellow-green and brown skeletal covering and are widely distributed in tropical and subtropical waters. Accidental contact is common and the intense pain can last from two days to two weeks. Fire corals have small nematocysts or stinging cells, similar to the nematocysts of jellyfish. In addition, fire corals, like many corals, possess a sharp, calcified external skeleton that, upon contact, can scrape or cut the skin.
Perhaps the most dangerous creature I’ve ever been around is an invertebrate: the box jellyfish of northeastern Australia. Forget sharks. The Indo-Pacific or Australian box jellyfish (Chironex fleckeri) is the most venomous marine animal known to science (Sutherland, S. 1980. Family Guide to Dangerous Animals and Plants of Australia. Sydney: Rigby Publishers).. The box jelly produces an excruciatingly painful sting, which is often fatal. This organism inhabits Australia’s northern coastal areas year round. However, it is particularly dangerous during the wet season, from about November to April. Box jellies have dozens of tentacles and each tentacle has many thousand stinging cells or nematocysts, which are are activated upon contact. Stings from these nearly transparent animals are extremely dangerous, primarily due to their effect on the heart; it’s not uncommon for victims who have had a severe sting to go into cardiac arrest within minutes. The pain from a sting is reportedly so excruciating that a victim can also die of shock.
In late summer, the adult box jellyfish spawn at the mouths of rivers. The eggs, once fertilized, turn into tiny polyps that attach themselves to rocks where they develop until the following spring. In spring, the polyps transform into tiny jellyfish that are washed downstream with the summer rains. The only treatment for a sting is to apply normal vinegar over the tentacles, which inactivates the nematocysts. Many popular Australian beaches where box jellyfish are present have a bottle of vinegar stored on the beach next to warning signs, and this has saved dozens of lives. Even though box jellies do not favor deep water over coral reefs, they have occasionally been found there. When snorkeling or scuba diving on the Great Barrier Reef, dive operators strongly suggest wearing a lycra dive skin to prevent contact with the tentacles. I wore one last time I was diving and snorkeling in Queensland in 2008. As I said earlier, when it comes to dealing with poisonous or venomous animals, the more you know, the better.
Jordan: What about injurious species of invertebrate and vertebrate fauna that can harm wildlife professionals? From the improper handling of scaled bony fishes to the incisors of rodents and beaks and talons of predatory birds –large and small–some of the seemingly benign or seemingly innocuous species in the animal kingdom present surprising hazards to humans working with these creatures. Can you talk about these concerns?
Michael: Most species of animals have some form of defense and can fight back when threatened, even the seemingly innocuous. The type of danger involved depends on the weaponry a given species possesses and how such weapons are used. Even the diminutive deer mouse (Peromyscus spp.) can inflict damage by biting with its large incisors. The normally peaceful beaver (Castor spp.), has recently been implicated in human deaths (http://www.huffingtonpost.com/2013/04/12/beaver-bites-man-to-death-belarus_n_3064822.html; http://www.foxnews.com/us/2012/08/13/rabid-beaver-attacks-new-york-man-swimming-in-pennsylvania-river/). Male deer and elk have sharp antlers are can be hyper-aggressive during the mating season or rut and have been known to attack people (http://www.thewildlifenews.com/2011/10/03/passers-by-rescue-women-from-mule-deer-attack-near-preston-idaho/). Great care must be taken when handling predatory birds, such as eagles or hawks, as the sharp talons on their feet can inflict injury (http://wildpro.twycrosszoo.org/S/00Man/AvianHusbandryTechniques/UKBHusbIndTech/handle_av_birds_of_prey.htm). Wild horses, such as zebra, can bite and deliver powerful kicks with either their fore- or rear legs (http://www.thesun.co.uk/sol/homepage/news/2487133/Zebra-kills-Brit-woman-on-safari.html). Red kangaroos may seem relatively benign, but can also be aggressive and inflict severe injury by kicking with their powerful rear feet (http://travel.cnn.com/sydney/visit/kangaroo-attacks-old-woman-confronts-police-040822). Bony fish, such as bullhead catfish (family Ictaluridae) can inflict wounds if not handled properly. All catfish have sharp barbs on their pectoral fins that inject venom when they jab an enemy. Catfish “stings” are no worse than insect bites for humans; however they can be painful. The list goes on and on. When in nature, people need to respect wild animals and not treat them as glorified pets. Animals will defend themselves if they feel threatened. Habituated wildlife—those that have lost their fear of humans– are often even more dangerous (http://newswatch.nationalgeographic.com/2013/03/09/human-wildlife-conflict-an-interview-with-dr-michael-hutchins/ ).
Wildlife experts spend many years learning how to properly and safely restrain and capture wildlife for veterinary care, research, population control, and transport. As a curatorial intern in the Mammalogy Department at the Bronx Zoo in New York in the late 1980’s, I used to go on rounds with the veterinarians. It was my job to work with the keeper-supervisors to capture and restrain various animals as necessary. In this role, I handled virtually everything in collection, ranging from Patagonian cavies (Dolichotis patagonum), to non-human primates to snow leopards (Panthera uncia) to native and exotic ungulates, such as bongo (Tragelaphus eurycerus), gaur (Bos gaurus) and American bison (Bison bison). In many cases, larger, potentially dangerous animals (e.g., tigers, snow leopards, gorillas) were anesthetized by the vets before being handled, but in others, the animals were captured and restrained by hand. I became very skilled at using nets, ropes, and variety of other tools of the trade.
While conducting fieldwork in Olympic National Park, I assisted in capturing, restraining, and tagging nearly 300 Rocky Mountain goats (Oreamnos americanus). We accomplished this with the use of rope foot snares placed near a salt lick where the animals gathered. When an animal placed a rear foot in the noose, it was pulled and the rope tightened around the leg, preventing the animal from moving. The rope was held taught until another individual could approach the animal from behind, grab it by its horns, and pull it down on its side, where it was subsequently blind-folded and hobbled. Measurements and samples were then taken and the animal was tagged and released. Great care had to be taken to avoid the dagger-sharp horns that both sexes of mountain goats have on their heads. Of course, even experts sometime make mistakes. On one occasion, I tried to catch a large male by myself; the rope wrapped around my wrist and pulled me to the ground. I was dragged for several yards over loose gravel until I hit a large rock with my back, and the rope broke. That was fortunate for me, as the goat went over a ledge and down steep rocky terrain. Although I was not seriously injured, I was pretty beat up and had to take a few days off to recover.
In 1988, I assisted with the capture, measurement and tagging of 2,000 Megellanic penguins (Spheniscus magellanicus) at Punta Tombo in Patagonia, Argentina. Penguins can deliver nasty bites with their sharp bills, and fortunately, I was only nipped once during the time I was there. We used specially-built, metal hooks to catch the birds by a leg and pull them out of their nests, and then restrained them by hand. A sling held the birds in place while they were being weighed.
In my own neighborhood, I have occasionally caught large snapping turtles (Chelydra serpentina), primarily to get them out of a road where they could be run over by traffic. These animals must be carefully handled by their shell, rear feet and tail, in order to stay as far away from the mouth as possible. Being bitten by one of these powerful reptiles would be extremely painful, as they have strong jaws and once attached do not let go.
As noted above, capturing and restraining potentially dangerous wild animals is a job for experts, not for the inexperienced layperson. Many a compassionate person with good intentions has been seriously hurt or contracted potentially fatal diseases by trying to catch or restrain wild animals (http://fox4kc.com/2012/04/14/woman-bit-trying-to-help-injured-bobcat/; http://news.yahoo.com/blogs/sideshow/oregon-man-contracts-plague-trying-rescue-mouse-cat-231942207.html).
Jordan: More obvious hazards are the “dangerous beasts”, which include the likes of lions, tigers and bears. Can you discuss the hazards of working around free-ranging wild animals like bears and big cats?
Michael: Most people are well aware of the dangers associated with large carnivores. Working with or around these animals requires special precautions. Although attacks are comparatively rare, they do occur and should not be taken lightly. I outlined some of these potential dangers in my interview on human-wildlife conflict (http://newswatch.nationalgeographic.com/2013/03/09/human-wildlife-conflict-an-interview-with-dr-michael-hutchins/), so will not go into great detail here. Suffice to say, that such animals should be admired from afar, rather in close proximity (see Hutchins, M. 2007. Grizzly man: The life and death of a misguided wildlife lover. The Wildlife Professional 1(1): 38-39). Wildlife experts who work on or around these animals are sensitive to the dangers and their knowledge of animal behavior often helps them to avoid direct confrontation. For example, danger from grizzly bears (Ursus arctos horribilis) is most intense in the spring when females have young cubs (Herrero, S. 1985. Bear Attacks: Their Causes and Avoidance. New York: Nick Lyons Books). Female grizzly bears are highly protective of their young, a behavior which has evolved because of the significant threat that adult male bears pose to their cubs. Males will, in fact, kill and cannibalize cubs if an opportunity presents itself. Consequently, chance encounters between humans and female bears with cubs are by far the most dangerous. I was in Yellowstone in 2010 for an invited workshop on wildlife health in the Park. On one afternoon, they loaded us in a bus and took us for a tour. We stopped at one location and got out of the bus to look at the view. Our host told us that this had been the site of a bear attack just a few months earlier, and subsequently recounted the story. The victim, who was a serious photographer, had gotten out of his car and set up his tripod about 50 meters from the road. He was in the process of photographing a female bison and her newborn calf, when he suddenly looked up from his camera lens. There, immediately in front of him, was an adult female grizzly and her cubs. Within seconds, the bear reared up and struck the man on the head with her huge paw, literally ripping the skin off his skull and face. This was obviously a defensive reaction, as she immediately left the scene with her cubs. Seriously injured, the man was able to crawl back to the road, where a Good Samaritan found him and rushed him to the hospital. He survived, but this example illustrates what can happen if sufficient precautions are not taken. First of all, this was a time when many grizzly bears were frequenting the area to search for vulnerable bison calves. Second, the man was alone and too far from his vehicle. And third, he was focused on his photography, rather than being intensely aware of his surroundings.
While hiking or working in grizzly bear country it is advisable to be aware and to make a lot of noise, as bears do not like to be surprised. If there is no escape from a bear, people are advised to drop to the ground, remain motionless and protect the head (Herrero, S. 1985. Bear Attacks: Their Causes and Avoidance. New York: Nick Lyons Books). Though bites may still occur, the animals may soon lose interest and leave. I have met two people who had been attacked by grizzly bears and survived. One was a Canadian scientist who had worked on bears and was mauled while letting a bear go from a culvert trap. Another was a ranger, who had been severely mauled by a bear in Glacier National Park. While both had visible scars, they both survived to tell their stories. Neither held any animosity towards the bears that had attacked them, noting that the animals were just being animals and trying to protect themselves or their offspring.
You mentioned bears and big cats when you asked the question, but you didn’t mention crocodilians—large reptiles, which I believe to be among the most dangerous animals on the planet. I have spent a considerable amount of time in crocodile country, primarily in northern Australia, Indonesia and East Africa. The closest I’ve ever been to them was in Kakadu National Park, Northern Territory, Australia. There are many large salt water crocodiles (Crocodylus porosus) inhabiting the streams, waterholes and wetlands of this region. An adult salt water crocodile may reach 14-17 feet in length and weigh 880–2,200 pounds. They are opportunistic predators that are capable of taking nearly any prey that enters their territory, including humans (http://www.smh.com.au/national/recent-crocodile-deaths-in-australia-20090411-a3b2.html). While walking near water in crocodile country, one must remain hyper-aware. Going in the water, however, even wading knee deep, is ill-advised.
Having taken many trips to East Africa, I have been in close proximity to lions (Panthera leo) on several occasions. On my last trip to the Serengeti in 2011, my guide and I spent several hours following and observing a pride of 15 lions, including two large males, several adult females and young. We were in an open-topped vehicle and at one point, a line of female lions strolled lazily by us within a few feet. As each animal went by, they quickly glanced up at me. I must say that this sent a chill up my spine and my heart racing, as I knew perfectly well that anyone of them could have joined me in the vehicle in a split second. Fortunately, the Serengeti lions are used to vehicles and see them as just another neutral aspect of their environment. That being said, no one should ever take chances with large predators, or assume that they will not act like predators if given a chance. When it comes to large carnivores, caution is the better part of valor.
Jordan: Vector-borne diseases and other communicable diseases have been addressed in an earlier interview that you graciously participated in. Since I just got back from India, where I suspect more field biologists have succumbed to vector-borne disease agents than encounters with their study subjects such as elephants and rhino and big cats and bears, I’d be curious to hear you elaborate on some of these concerns for the wildlife professional?
Michael: Since I dealt with some of these hazards in a previous interview (http://newswatch.nationalgeographic.com/2013/03/22/the-threat-of-emerging-and-re-emerging-infectious-diseases-to-wildlife/), I won’t go into a lot of detail here. Suffice it to say that people who spend a lot of time in the outdoors or handling wildlife are at risk of contracting various diseases or parasites, some of them potentially fatal (Thomas, M. 2012. Danger: All if a day’s work: The inherent risks of the wildlife profession. The Wildlife Professional 6(1): 58-61). First and foremost are probably diseases that come from being bitten by blood-sucking insects, such as mosquitos and ticks. In much of the world, malaria is still a major threat and some strains have become resistant to anti-malarial drugs (http://www.cdc.gov/malaria/about/index.html). Wildlife professionals and laypersons alike must be concerned about a host of other mosquito-borne diseases as well, including West Nile virus, encephalitis, and dengue and yellow fever, especially since their incidence seems to be increasing as a result of global climate change (http://adventuresportsjournal.com/blogs/earth-talk/mosquito-borne-diseases-on-the-uptick-thanks-to-global-warming ). Ticks also carry a number of dangerous diseases, such as Rocky Mountain spotted fever and Lyme disease (http://www.cdc.gov/ticks/diseases/). There are prophylactic drugs that help prevent malaria (http://www.washingtontravelclinic.com/malaria). However, the best defense against malaria and other insect-borne diseases is simply not to be bitten. Using a combination of clothing to cover the skin, along with insect repellent and insecticides, it is possible to avoid being bitten altogether. Serious travelers to the world’s tropical regions often purchase a powerful insecticide, which can be sprayed on clothing to provide an extra layer of protection. In addition, it is important to sleep under a mosquito net. Night is a time when mosquitos are active and netting provides extra protection during this period of increased vulnerability.
Some blood-sucking creatures do not pose a health threat, although they can be an annoyance. Leeches are common in many areas of the world (https://en.wikipedia.org/wiki/Leech). Some leeches are found in freshwater and only become attached if one becomes immersed in water. I’ve pulled numerous large leeches off my legs after hiking through knee-deep standing water. I’ve also been in tropical areas of the world, including the jungles of Malaysia, Indonesia and northeastern Australia, where land leeches are common. Standing still in the forest, one can literally see the ground moving toward you, as the leeches detect your presence and start inching toward your position. The bites cannot be felt, as leeches possess a natural anesthetic and anti-coagulant in their saliva. After hiking through the Australian rainforest one night in 1985, I literally poured blood out of my shoe. Fortunately, leech bites, though annoying and itchy when healing, are not dangerous, as leeches pass no known diseases to humans.
There are many other disease-related issues that wildlife professionals must be concerned about. For those who work with bats and smaller carnivores, such as skunks and raccoons, rabies is a constant threat. In fact, everyone should be aware of wildlife that is exhibiting unusual behavior. I was once hiking down a riverside trail in mid-day near Philadelphia, Pennsylvania with a friend. From a distance, we saw an adult raccoon (Procyon lotor) wandering erratically during midday and vocalizing loudly. These are potential signs of a rabid animal, so taking no chances; we walked quickly in the opposite direction, avoiding any contact with the animal. Raccoons are a primary reservoir for rabies, a disease which if left untreated, is nearly always fatal.
Parasites are another potential threat. For example, wildlife professionals who work with wild dogs (e.g. wolves, foxes and coyotes) and other wildlife must be aware of and protect themselves from hydatid disease. This is a potentially fatal parasitic disease caused by tapeworm of the genus Echinococcosis. The adult tapeworm lives in the canid’s intestine and produces eggs that are passed in feces. The intermediate hosts are infected by ingesting eggs. Sheep, wild herbivores and rodents are the usual intermediate hosts, but humans can also be infected. The egg hatches in the digestive system of the intermediate host, producing larva, which then penetrate the intestinal wall and are carried by bloodstream to liver, brain, lung or other organs. Once settled in an organ, it turns into hydatid cyst. Humans can become infected by handling soil, dirt or animal hair that contains eggs (http://en.wikipedia.org/wiki/Echinococcosis). There are currently no effective drug treatments or vaccines to protect humans against this potentially fatal disease. This parasite has worldwide distribution and is being seen in North America with increasing regularity. The majority of documented human infections in the United States to date have been acquired overseas in areas where the disease is endemic. However, a paper published in 2009 (Foreyt et al. 2009. Echinococcus granulosus in gray wolves and ungulates in Idaho and Montana, USA. Journal of Wildlife Diseases 45(4):1208–1212) reported finding the parasite in 62% of Idaho wolves (Canis lupus) evaluated between 2006 and 2008; the parasite was also detected in elk, deer, and mountain goat. Well-known wildlife biologist, Dr. Valerius Geist, has been warning the public and wildlife practitioners about this disease for some time (http://www.idahoforwildlife.com/Website%20articles/George%20Dovel/The%20Outdoorsman%20No%20%2037%20Jan%202010.pdf), but his warnings have often been discounted or ignored by public health officials and the public.
People who handle reptiles and amphibians, such as snakes, turtles and frogs, must always be concerned about Salmonella, a bacteria that, when ingested, can cause serious illness (http://www.cdc.gov/Features/SalmonellaFrogTurtle/). Reptiles and amphibians are natural reservoirs for Salmonella and washing one’s hands after contact is a prudent precaution. Similarly, zoo professionals must take special precautions when working with non-human primates. Because they are so closely related to humans, many diseases are easily transmittable between species, including hepatitis, herpes, tuberculosis and wide variety of other maladies (http://www.aphis.usda.gov/import_export/animals/oie/downloads/tahc_sep12/tahc_zoonoses_transmit_from_non_human_primates_81_sep12.pdf). When working with primates behind the scenes, keepers typically wear surgical gloves, masks, and wash their clothing on site. To prevent the spread of disease from one animal facility to another, zoo keepers and others entering and leaving the facility are often required to step into a tub of disinfectant.
Wildlife professionals are at particular risk of disease when conducting field necropsies of dead animals. One cautionary tale deserves mention. In 2007, Eric York, a National Park Service biologist, who conducted a field necropsy of a mountain lion (Felis concolor) carcass in Grand Canyon National Park, later died from pneumonic plaque. The Centers for Disease Control later concluded that York had contracted the disease from the dead animal (Thomas, M. 2012. Danger: All in a day’s work: The inherent risks of the wildlife profession. The Wildlife Professional 6(1): 58-61).
Jordan: Just getting to a field site is often a serious hazard in itself. Far more biologists have been killed in transit to remote, rustic and even accessible locations not far from their offices. These unfortunate and tragic incidents far outnumber lethal encounters with their wildlife subjects. Can you talk about this?
Michael: In order to have access to remote sites or to survey wildlife populations, wildlife professionals often have to rely on small fixed wing aircraft and helicopters, which can be dangerous. In an article reviewing the dangers associated with the wildlife profession, author Madeleine Thomas (Thomas, M. 2012. Danger: All in a day’s work: The inherent risks of the wildlife profession. The Wildlife Professional 6(1): 58-61) identifies flying as the riskiest activity for biologists, accounting for 66% of all mortalities. Collisions with power lines, strong winds, and mechanical failures were the most frequent cause of accidents in airplanes and helicopters. I have flown in helicopters and small fixed wing aircraft on numerous occasions in the U.S., Iceland and Africa. Helicopters are highly maneuverable and can hover and land virtually anywhere. As such, they are incredible tools for conducting wildlife surveys in rugged terrain. But, they also do not leave much room for error; in the case of mechanical failure, which includes engine stalls, they cannot glide to safety. I flew with a contracted pilot to conduct a mountain goat survey in Olympic National Park in 1981. A seasoned Vietnam veteran, the pilot in question had complete command of his aircraft. Just to illustrate how hazardous flying a helicopter is, less than a week after I flew with him, he died in a helicopter accident lifting an air conditioning unit into a shopping mall in Seattle.
Of course, driving or riding in a vehicle is also hazardous. There are tens of thousands of collisions and single car accidents annually, and hazards such as wet roads, deer (there are over 1 million deer-vehicle collisions in the U.S. annually), and drunk or aggressive drivers are far too common. A failure to handle dangerous field equipment, such as ATVs, traps, dart guns, chainsaws and the like, can also cause injury or death in wildlife and other natural resource professionals. The National Park Service has the highest rate of accidents and mortality within the Department of the Interior. In the past 25 years, nearly 60 park rangers and employees have died while on the job (Thomas, M. 2012. Danger: All in a day’s work: The inherent risks of the wildlife profession. The Wildlife Professional 6(1): 58-61).
Can you talk about the poisonous plants that also present serious hazards to people working outdoors?
Michael: Yes, there are many plants, both native and non-native, that can pose danger to those venturing into the outdoors, whether they are wildlife professionals or laypersons. Perhaps the most dangerous plant I’ve ever been around is the so-called “stinging tree” (Dendrocnide moroides) of Australia. This is a large shrub native to the rainforests of northeastern Australia (Queensland), the Moluccas and Indonesia. It is best known for the stinging hairs, which cover the whole plant and deliver a potent neurotoxin when touched. Contact with the leaves or twigs cause the hollow, silica-tipped hairs to penetrate the skin, where they can move into the bloodstream. The sting causes extreme pain, which can last for months, and the injured area becomes covered with small, red spots that combine to form a red, swollen mass. The sting is known to be potent enough to kill humans, dogs and horses. The recommended treatment for skin exposure is by pulling the hairs out with a wax hair removal strip. One of the first things you learn when hiking in Queensland’s tropical rainforests is to identify the distinctive heart-shaped leaves of this plant and to avoid it like the plague. Unfortunately, stinging trees are an early colonizing plant that is commonly found along the edges of hiking trails, necessitating constant vigilance. In such areas, it is often best to stay on the trails.
In North America, people who spend a considerable amount of time outdoors must be on constant alert for poison ivy (Toxicodendron radicans) and poison oak (Toxicodendron diversilobum). While I’ve never encountered poison oak, I’ve certainly had some horrific experiences with poison ivy. Even the slightest contact with this plant can result in a skin rash called allergic contact dermatitis. The red, extremely itchy rash is often accompanied by fluid-filled blisters. The rash is caused by contact with an oil called urushiol, which is found in poison ivy and oak. The oil is present in all parts of the plants, including the leaves, stems, flowers, berries, and roots. The rash is actually an allergic reaction to this oil. Indirect contact with these oils can also cause the rash, such as occurs when one touches clothing, pet fur, or other objects that have come in contact with one of these plants. Not everyone is allergic to these oils; some people are immune to their effects or have a limited reaction. Clearly, anyone who spends time outdoors should learn to recognize these plants and avoid them. Given my past unpleasant experiences with poison ivy, I am highly sensitive to its presence while hiking through forested areas. I also wear long pants, even when it is uncomfortably warm. When contact with the skin occurs, the only treatment is to wash the area with a special, widely available abrasive soap that dissolves and removes the oils before the allergic reaction can gain momentum.
A dangerous introduced plant that has gotten a lot of recent attention is the giant hogweed (Heracleum mantegazzianum). The sap of this plant, in combination with moisture and sunlight, can cause severe skin irritation, painful blistering, permanent scarring and even blindness if the sap gets into the eyes. Contact between the skin and the sap of this plant occurs when people brush against the bristles on the stem or break the stem or leaves. Giant hogweed is a native of Eurasia, ranging in the Caucasus Mountain region between the Black and Caspian Seas. It was introduced to Europe and the United Kingdom in the late nineteenth century and purposefully brought to the United States in the early twentieth century, remarkably as an ornamental garden plant. It has since become established in New England, the Mid-Atlantic Region and the Northwest (http://www.dailymail.co.uk/news/article-2011541/Giant-hogweed-cause-BLINDNESS-invades-New-York.html ). Giant hogweed grows along streams and rivers and in fields, forests, yards and roadsides.
Plants that have sharp spines should also be avoided, as they can penetrate the skin causing lacerations. In the U.S. desert southwest, great care must be taken around cactus as contact with the sharp spines, though non-toxic, can be extremely painful. Most species of cacti have spines, which are highly modified leaves. While their primary function is to defend against herbivores, spines also help prevent water loss by reducing air flow close to the cactus and providing some shade. There are many other plants that have sharp spines and projections. I remember encountering some long, thin, spiny vines in the jungles of Indonesia. Often they would hang down in the middle of the trail; difficult to see, they would suddenly hook the skin on your face and draw blood as you continued to walk forward. Blackberry vines (canes), with their sharp, curved thorns, can cause similar discomfort if encountered while hiking.
Jordan: Clearly, the great outdoors is not always the safest venue in which to work. We have thus far addressed biological hazards, but what about physical hazards? Falling out of a tree and succumbing to fatal injuries or drowning in a river are not uncommon, nor are hazards associated with inclement weather, from freezing to being struck by lightning. I remember my efforts to capture and restrain California sea lion pups on island rookeries in the Sea of Cortez. Talk about trying to navigate challenging terrain in a hurry—forget about the biological hazards in the water and on land like adult sea lions and sharks. Biological hazards are one thing, but the physical hazards of working outdoors can also be problematic. Can you elaborate on these concerns?
Michael: Certainly, physical hazards are another danger that wildlife professionals and anyone venturing into nature must be concerned about. When I was working at 8,000-feet elevation in the Olympic Mountains studying an introduced population of Rocky Mountain goats, I was particularly concerned about lightning and falls in the rugged, rocky terrain. In high elevation subalpine meadows, you are typically the tallest thing standing, which means you are a natural lightning rod. During severe thunderstorms, I would often head down to lower elevations and hike back in the next day or a few days later. Falls were another constant threat. Despite constant warnings not to follow the goats into steep terrain, one of my field assistants walked out onto a steep snow bank, lost his footing, slid for several hundred feet and then crashed into a rock, which broke both of the bones in one of his legs. He had to be carried out on a stretcher. Fortunately, that was the only serious injury that any of my field assistants had in over four years of field work. That being said, we witnessed injuries in hikers that roamed through the area, broken legs being the most common. Often these would occur in spring, when the snow was melting. One thing experienced field workers learn is to avoid the areas around exposed rocks. As the darker-colored rocks heat up, melting can occur under the surface and be undetectable to a hiker. If one steps too close to the rock, a leg can penetrate the upper layer of snow and subsequently result in a break or a fracture. In the vicinity of cliffs, falling rocks or collapsing soils are also potentially dangerous. This is precisely why working in the field alone is not a good idea. It is always best to have a companion or colleague to ensure that help can be summoned if anything goes wrong.
Working at high elevations or in any cold climate, one of the most insidious dangers is exposure. Without sufficient layers of clothing and protection from wind and cold weather, your body temperature can drop very rapidly and send you into shock. Working in subalpine and alpine areas, it is therefore always necessary to have dry clothing to change into if necessary. A wet body loses heat faster than a dry one. Having a tent and a thick sleeping bag to protect you from lower nighttime temperatures and wind is also a necessity. Extreme cold, such as occurs in polar regions or at extremely high elevations, requires even greater precaution, including specially-designed clothing and a reliable heat source.
Of course, extreme heat can be problematic as well. In warmer climates, it is important to limit direct exposure to the sun and to hydrate frequently. A failure to do so can result in severe heat stress, dehydration and loss of consciousness. Access to water is therefore essential. While assisting with a feral domestic cat research project in the Galapagos Islands in 1979, four of us climbed Darwin Volcano on remote Isabela Island. It was a three-day trip, and since there is no fresh water on the island, we had to carry seven and a half gallons of water with us, as well as a limited amount of food. For three days, we survived on rations of British tea biscuits and chocolate. On the way to the summit and back, we hiked over broken plates of sharp a’a lava in 90-degree weather with no shade. We did our best to ration our water intake. It was fascinating to see how the body adapts—urination becomes infrequent and little is produced. On our way back to camp at Tagus Cove, we had only one quart of water each. We started back as soon as there was first light and hiked all day. I had gone through all of my remaining water by noon, and we did not arrive back at the camp until around dinnertime. I couldn’t work up one drop of spit in my mouth for several hours and began to feel a bit disoriented. That was as water stressed as I have ever been.
Protection from the sun and its UV rays is also important, particularly in desert or high elevation habitats. Sunburn is known to lead to skin cancer and can be extremely painful. It is therefore prudent to use sun block and to cover the body with protective clothing, including a hat. Sun glasses are also essential to protect the eyes.
Water is another potential hazard. In the desert, one must be particularly careful not be caught in a flash flood. Thunderstorms in arid areas, although rare, can send torrents of water rushing down narrow canyons, thus threatening anyone who is present. In coastal areas, rip tides are a potential threat, as well as rare but deadly tidal waves. In rivers and streams, the primary hazards are depth and strength of flow; fast moving water can pull you under and must be respected. While working on boats of any kind, it is important to have floatation devices either on or handy in case of emergency. Of course, it doesn’t hurt to be a strong swimmer if one intends to work or recreate around water. As a certified scuba diver, I am well aware of the many potential risks associated with that sport, including equipment failure, inner ear injuries, entanglements, strong tides, inadequate air supply, disorientation and the bends. All of these hazards can be avoided with good training and good sense. Scuba divers are taught never to panic, as that can lead to many problems. We are also taught a standardized set of emergency signals, how to buddy breath and to never dive alone.
Given the potential hazards associated with the wildlife profession, the public is lucky to have so many dedicated individuals willing to put their health and lives at risk. Wildlife professionals truly love what they do, but do not receive extra hazard pay associated with their jobs. Perhaps Congress and others could remember that next time they decide to cut back on their hours or pay.