Wildlife Corridors

Posted by xdhaas on 25 May 2012
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You may have noticed that I talk a lot about habitat fragmentation, whether by roads, fences, or entire human communities.  There’s a reason for that; it’s a huge and very common problem.  As I’ve mentioned in the past, habitat fragmentation causes a lot of problems for wildlife such as reduced resources and a reduction in genetic diversity.  Due to these major issues, one of the things that has always interested me is wildlife corridors.

Wildlife corridors can take many forms.  Those bridges or tunnels that allow animals to reach habitat on the other side of a fence or a road qualify as corridors, though they can be much larger.  A wildlife corridor is basically a strip of land that allows wildlife to go from one patch of habitat to another.  Sometimes suitable habitat is not only a few meters away, but miles away instead, and animals still need access.

Many times when a corridor is constructed it is focused on a target animal, meaning a main focus species, such as a jaguar.  That doesn’t mean only this animal would use the corridor but that certain larger species are focused on as they may require more territory and may also be popular with humans, which is often necessary to gain support, approval, and financing to construct a corridor.  Often called an “umbrella” species as well, focusing on a larger animal will help the other animals within the community, extending protection and opening up new resources.

Keeping a natural wildlife corridor open and available for wildlife takes proper management and safeguards.  Designing a wildlife corridor from scratch takes a completely different focus.  In this case one must be constructed, which takes more planning and money than if nature has already proved one that has yet to be overtaken.  Approval must be obtained, which involves a lot of governmental red tape, and public support is always a large benefit.

Designing wildlife corridors requires an understanding of the target species.  It must contain suitable habitat and resources and must be large enough so that the animal will use it.  Smaller species, for example, won’t use an area that doesn’t provide sufficient coverage from predators.

For larger projects Geographic Information Systems (GIS) are used.  This is a type of system that is becoming more and more common in the wildlife and conservation fields and it would help any students or professionals within these fields to at least have a general understanding of it.  I will talk more about GIS and conservation next week, but for now, just know that GIS is a system designed to capture, store, manipulate, analyze, manage, and present all types of geographical data.  And what are we looking at when we’re constructing wildlife corridors or habitats?  Geographic data!  Perfect fit.

While wildlife corridors can be found all over the world, the one I am most familiar with is in South America and focuses on jaguars (Panthera onca).  It is called, fittingly, the Jaguar Corridor Initiative championed by Panthera, an organization focusing on the conservation of wild cats.  This consists of not one corridor but many, stretching across several countries, from Argentina to Mexico.  Encompassing so much territory, these corridors cut into areas where civilized humans live.  They can cross plantations, jungle, ranches, grasslands, and more.  Many of these corridors are not yet real, safe corridors, but ideas and plans scientists and supporters are striving for.  Working with GIS systems to map out the areas, tracking devices, witnesses, and hard evidence  track jaguar movement, showing the natural patterns of the animals and where the most effective corridors should be located.

Getting the movement patterns of the jaguars and the geography of the areas is just the beginning.  Once areas have been identified, the hard work begins.  Education and outreach is necessary as many people do not want these cats in their neighborhoods and community support is vital.  Government support needs to be won.  Financing to create, maintain, or reclaim the corridor needs to be found, whether through grants, donations, or other sources.  Human-jaguar conflict reduction strategies must be learned and implemented to reduce tensions and make the corridors safe for all involved.

From the little salamander to the giant elephant, access to natural resources and others of a species is imperative.  Wildlife corridors can be hard work, but in a time of fragmented habitats, these corridors are necessary to ensure the survival of not only the focus species, but the community at large.

The Fence: Friend or Foe? Part 3

Posted by xdhaas on 18 May 2012
Posted in: Explanations, Issues. Tagged: , , , , . 1 comment

In many parts of the world animals are killed on roads every day as they attempt to cross.  Roads fragment habitat but that doesn’t mean animals don’t try to reach the other side, where they may find more food, water, mates, and shelter.  Motorized vehicles make stretches of pavement very dangerous as the animals are often unable to get out of the way in time or are paralyzed in fear.  We’re not talking about a horse and buggy here but vehicles that can move very quickly, and often do.  It saddens me to see an animal dead on the side of the road, but it is a common sight.

In many places fences are used to try and block access to roads in order to prevent mortalities.  The type and size of the fence depends on the animals in the area.  Animals are also resources and a fence or wall may not deter them all from attempting to break through and make the dash.  Yet, these fences may work for many areas, for many animals, and keep them safe from the deadly impact of cars and trucks.  Of course, this can have the same effect as the road itself, dividing a habitat and bottlenecking the community. 

But all is not lost.  Various methods of animal crossings have been proposed and put into practice.  Fences may not just block access to a road but they can also funnel the animals to a spot that is safer to cross, whether that spot is a tunnel beneath the road, a bridge over it, or a spot in the road that has lower volumes of traffic, slower speeds, or has sensors to warn drivers of approaching animals.

Fences can also safeguard habitat from human trash.  Unfortunately I often seen garbage on the sides of roads from drivers and passengers throwing their trash out of car windows with little regard to where it lands.  Fences can block garbage from entering sensitive habitat such as wetlands while making it easier to pick up by clean-up crews.

On a smaller scale private fences fragment and block off habitat as well, limiting wildlife traffic and their resources, preventing access to food, water, and rest areas.  I know, since my neighbor moved in and put up a fence to keep in his birds and children, that we’ve had a drastic reduction in wildlife visiting our yard.  Whereas white-tailed deer (Odocoileus virginianus) used to be common, now I’ve only seen them in the field once.  I haven’t seen the fisher (Martes pennant) or fox in months.  Actually, the only new animal I’ve seen were guinea hens, and those were escapees from the neighbor’s yard.  At the same time, fences can protect precious pets from predators while protecting prey animals from our pets.  And as mentioned by my friend Stacy on Part 1, fences can also provide a way for squirrels to run from one area to another while staying off the ground and away from certain predators, and I’ve also seen birds resting or even nesting on posts.

Now, many animals can jump fences.  Deer, for example, are hard to keep out of an area if they really want in, but they don’t always want to put in the effort.  Rabbits and other smaller species can sometimes dig under fences, much to the pleasure of your dog, and certain types of fencing can be squeezed through.  However, certain types of fences are more wildlife-friendly than others (there are actually businesses out there promoting such fencing).  Animals can get caught in fences, particularly those made of wire, which are more difficult to see, and can lead to their injury or death.  I’ve also seen animals such as dear try to jump wrought iron fences and getting caught or impaled.  It is just this type of wire fencing that can be seen strung out for miles.

When it comes to something like a fence it is not a black and white issue as to how it may affect wildlife and their habitats.  Sometimes that fence can harm while other times it may save.  One type of fence in one area may trap animals while another type of fence in the same spot could help them or not hinder them.  If such structures are to be set up, care and thought should be put into their impacts.  Identified negative wildlife impacts could be corrected just by changing the type of fencing, or perhaps a fence isn’t really needed at all.  Our decisions have impacts far beyond just us and it’s important to keep these things in mind.

The Fence: Friend or Foe? Part 2

Posted by xdhaas on 11 May 2012
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While in South Africa we spent time discussing the fences used around the national parks.  Many of them were electric fences because elephants would otherwise just knock them down with their bulk.  Fences were also put through rivers, across roads, and even through open savanna that may have been lacking in “development” but was still  not designated as part of the refuge and so was blocked off. 

The idea behind the fences here were interesting.  While talking to one of the guides he told us that, when people inquired about the fences, they were told the structures were there to keep the wildlife in and protect people.  But, he told us rather secretively, if you asked him, it was really to keep people out and protect the wildlife.  In all likelihood, it was probably a mix of the two.

People are often afraid of animals.  I’ve heard of city children that are absolutely terrified when they see their first cow.  People are afraid of a cheetah nabbing their children or a lion eating their goats or an elephant munching on their corn.  There are various ways to prevent this, of course, but for many people the easiest thing is to shoot the wildlife, or try to poison them, no questions asked.  Keeping wild animals in the preserve safeguards them from such behavior.  It is also a way to try and prevent poachers.  Fencing not only keeps the animals in, but helps keep the poachers out.  They still manage to find ways in, of course, but having a smaller area to survey does help rangers.  In addition, keeping wildlife in preserves gives them a designated area that is theirs alone, with little worry about invading humans using the area for the newest condo.

These wildlife preserves and national parks can make a huge difference in protecting species.  Sometimes a fence helps that.  If you are subscribed to my Twitter you may have seen the New York Times article I posted recently about the predator-proof fence put up across a piece of Oahu, a Hawaiian island.  The fence blocked off the Kaena Point Natural Area Reserve from the Kaena Point State Park. 

“Now, why would they want to do that?” you may be thinking.  To summarize the article, the birds of Hawaii were being ravaged by predators, most of which were introduced by humans.  Rats, cats, dogs, and mongoose were killing chicks, destroying eggs, and chasing adults.  The population was plummeting.  With the installation of the fence, however, the populations are taking off again.  The fence is as claimed, predator-proof.  After biologists and volunteers blocked the peninsula off and were able to go in and remove the predators, the area then became a safe refuge for birds to breed.

Not all fencing around preserves have such strongly positive impacts, however.  Kruger National Park has an overpopulation problem with their elephants.  African elephants are often killed by poachers for their tusks, so the successful breeding and reduction of poaching found in this park is an obvious benefit.  However, elephants are large creatures and have few natural predators.  A small calf may be stalked by lions, for example, but even that isn’t common because elephant herds are so protective of their young.  Hunter/gatherer humans would also on occasion hunt an elephant, but a single individual would provide so  much meat that such a large-scale hunt did not need to take place often.  One of the largest natural population controls for elephant populations is migration.  And now, with fences blocking the way, these animals cannot follow their instincts.

Migrations have generally occurred during the dry season of the area and the path taken is largely adhered to by the herd, a learned route passed down through the generations.  The path takes the family from area to area in search of food and watering holes.  The migration itself can be hundreds or even thousands of miles long and can be rough travel for very young, very old, sick or injured.  During very dry seasons there may not be enough food or water to ensure the health and survival of all members of the herd, and so many may perish along the way.

Keeping elephants in one area may seem like a good thing to some, as it prevents the long migration that may take the life of an elephant.  However, this cycle of life and death is necessary and healthy.  This is what the elephants evolved doing.  Restricting their movements to parks and preserves reduces their natural population controls, allowing for the population to get so large that the animals start destroying their habitat, and the habitat of others, as they strip vegetation in search of enough food to energize their huge bodies. 

Kruger is currently facing just a situation.  Their elephant population is double the recommended number of elephants for the area’s size and satisfactory methods of managing the population are still under discussion.  Chemical birth controls for over 14,000 elephants would be extremely difficult and expensive, yet the formerly used method of culling leads to public outcries.  With a fence preventing the normal population control method, what are we to do?

The Fence: Friend or Foe? Part 1

Posted by xdhaas on 4 May 2012
Posted in: Explanations, Issues. Tagged: , , , , , . 2 comments

Humans have been using various types of fences for thousands of years.  Huge stone walls have kept invaders out of cities since cities first formed while wooden stockades have surrounded villages, both permanent and temporary, even longer.  They were, and are, used for protection, to keep enemy tribes, thieves, and dangerous animals out of homes.  This basic use has since expanded.  Fences can be used around private houses or buildings but they also can encompass thousands of hectares of land, whether a preserve or farm.  Sometimes these fences are strung out thousands of miles/kilometers to separate entire countries in an effort to keep out illegal immigrants.  But walls and fences weren’t cutting across the habitat of most species while they were evolving.  How do these structures effect wildlife?

The Wildlife Professional, Vol. 5 No. 4, had an article, “Fenced Out: Wildlife Impacts Of The U.S.-Mexico Border Fence,” devoted to the effects of the U.S./Mexico border fence/wall the U.S. has been constructing, and the affect on wildlife of both countries.  The results are not promising.

The United States government has been installing massive walls and fences along it’s shared border with Mexico for two main reasons: to stem the flow of illegal drugs into the country and to prevent illegal immigrants from entering as well.  However, there are several large wildlife preserves on or near the southern border of the United States.  Many of the species found here are endangered and rare or are easily impacted by such large-scale habitat changes.  This massive wall is preventing animals from crossing from one area to another, fragmenting their habitat.  I previously spoke about the problems habitat fragmentation can cause, such as reduced resources, ecosystem changes, reduced genetic diversity and breeding partners, and more.  To heighten this damage, in most cases there is a certain distance from the fence that is cleared of all or most vegetation.

In 2005, the Real ID Act was passed.  A provision within this Act allowed for any laws that may delay the construction of the border fence/wall, such as environmental regulations, to be waivered.  Basically, it didn’t matter how much damage the construction of the wall, or the wall itself, may have on wildlife.  Recently an extension of this Act has been brought before the U.S. government that would expand the authority of border patrol units.  These new privileges would allow for border patrols to bypass any regulations limiting their activities in sensitive habitat, allowing both foot and vehicle patrols in areas that are easily damaged and not so easily repaired.

According to The Wildlife Professional article, many species are being impacted by this national border issue.  The Arroyo toad (Bufo californicus) and the California red-legged frog (Rana draytonii) would, or perhaps have, had their range cut down the middle.  The rare populations of jaguars (Panthera onca), ocelots (Leopardus pardalis), and Sonoran pronghorn (Antilocapra Americana sonoriensis) populations will be cut off from their Mexican breather.  Even birds such as the low-flying cactus ferruginous pygmy-owls (Glaucidium brasilianum cactorum) and various quail would be directly impacted by this construction.  There are many more species involved as well.

This is not to say that the border fence doesn’t provide at least some benefit to wildlife.  Illegal immigrants crossing into the U.S. aren’t generally concerned with the habitat they are crossing.  Backpacks, supplies, and garbage are often dumped with little regard.  It has also been estimated that illegal immigrants and drug traffickers have cut 8,000 miles of off-road tracks, both for foot as well as vehicle traffic, through wilderness.  Of course, it has also been estimated that law enforcement have added another 12,000 miles to this.

Then, of course, we might want to point out that despite all the effort in putting up this massive fence/wall, drugs and humans are still getting through it.  Slowing things down perhaps, but humans are determined creatures.  Perhaps an evaluation of the border should be undertaken.  Do the positives outweigh the negatives? 

I don’t want people thinking this is just a United States/Mexican issue.  Such borders can be put up anywhere and on smaller scales.  Each has a direct impact on wildlife.

Tapirs of the World

Posted by xdhaas on 27 April 2012
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It looks like everyone is lucky today because I’m giving you two posts!  I couldn’t help myself, I love the opportunity to talk about animals.  Today, April 27, 2012, is World Tapir Day!

Tapir are mammals that can be found in Central and South America as well as Southeast Asia.  There are four species of tapir: Brazilian tapir (Tapirus terrestris), Malayan tapir (Tapirus indicus), Baird’s tapir (Tapirus bairdii),  and the mountain tapir (Tapirus pinchaque). 

The largest of the tapirs, the Malayan tapir, can weigh up to 320 kg (704 lbs).  The smallest, the mountain tapir, can be as light as 136 kg (300 lbs), which is still pretty big.  The mountain tapir has a long wooly fur while the other three species have short fur, which makes sense given their environments.

The tapir snout is interesting in that it is like a miniature elephant trunk.  It can be raised up out of the water to use as a snorkel or it can help grab food.  You may notice from some of these pictures that their babies have interesting fur patterns, spots and stripes.  This is similar to a deer’s fawn, which also has a similar pattern.  These patterns have evolved to aid the young animal in escaping predators by camouflaging them, making them more difficult to see.  As they get older the pattern will fade and eventually disappear as they reach maturity.

Herbivores, these animals eat the fruits and vegetables found in their respective regions.  They are also crepuscular, which means they prefer to be active during dawn and dusk, when it is cooler and still fairly dim.  They use their speed and swimming ability to escape predators and cross their terrain in their search for food.

Unfortunately, all four species of tapir are considered endangered or vulnerable.  The main culprit?  Habitat loss and fragmentation.  As forests are cut to make way for housing complexes, ranches, and wood products, these animals are forced to rely on shrinking territory.  Poaching is also another serious threat as people may hunt this species both for food and for sport.  The Tapir Specialist Group is just one of many that are trying to conserve these species, both by raising awareness as well as supporting research by wildlife professionals.

Penguins of the World

Posted by xdhaas on 27 April 2012
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Wednesday, April 25, 2012, was World Penguin Day!  Check out  my wake-up call here at the Wildlife Web Watch’s blog: It’s World Penguin Day!  They have some cool fun facts all about penguins.

I really like penguins, though my experience with them is limited to zoos and the Discovery Channel.  Think about it.  Penguins, like other flightless birds, evolved from dinosaur-like ancestors to be able to fly, only to revert back to a flightless form when it proved to be an unnecessary adaption to their changing environments.  For penguins their flightless wings are perfect for swimming and their feathers have continued evolving in a way that helps insulate them and keep them warm even under the harshest circumstances.  That’s pretty cool in my opinion.  (Random, but here is a link to one of the cutest penguin videos I’ve ever seen, a ticklish baby penguin!)

When a lot of people think of penguins they probably also think of the freezing Antarctic.  Unless you live in the Southern hemisphere, that is.  If you do, and are near a coast, you might get to see real wild penguins right in your own back yard.  That’s because all penguin species only live in the southern hemisphere, yet they range from not only Antarctica but all the way up to the equator, and the Galapagos penguins (Spheniscus mendiculus) sometimes head a bit further north on their journey for food.

There are believed to be between 17 and 20 penguin species in the world today.  This is a great site with links to all of them.  They can be found not only in Antarctica but also in Africa, South America, Australia, and scattered among the many islands.  If you go to this map link the map is interactive and when you click on a location, statistics about the species of penguin found in that region will pop up.  Very nice.

The largest species is the emperor penguin (Aptenodytes forsteri), which has been made famous by movies such as March of the Penguins.  They live in the freezing Antarctic region and can reach a height of 115 cm (3.75 feet).  The smallest species is the little blue penguin (Eudyptula minor) which reaches a height of 30 cm (just under a foot).  A native of Australia and New Zealand, there are six subspecies of this bird.

Several years ago, while writing a paper for college, I came upon Professor P. Dee Boersma (University of Washington).  She’s spent more than 20 years studying the Magellanic penguin (Spheniscus magellanicus).  Her research over the years, which can be followed here at the Penguin Project and is sponsored by both the University as well as the Wildlife Conservation Society, has really let us into the world of these birds. 

Due to this long-standing research, Prof. Boersma, her staff, students, and volunteers have been able to track population dynamics.  What they’ve found is likely a representation of most other penguins around the world; the population is decreasing.  The two main causes for this is a lack of food (believed to be caused by humans overfishing) and the birds dying of starvation or hypothermia due to being coated with oil.  Oil?  Like in an oil spill?  Yes, that kind of oil, but oil and gasoline enter the water in many other ways than just a large scale spill.  Most of these dangerous substances enter the water due to runoff (it runs off land/roads from cars and other things and eventually finds its way into a water source), small ship leaks, and the releasing of contaminated ballast water from the hold of ships.

When a penguin becomes covered in oil it loses its ability to stay warm as the insulation properties of their feathers fail.  When penguins try to clean their feathers they end up ingesting some of the oil, which harms their stomach and intestines.  They are usually unable to clean themselves enough to seek out food or stay warm.

Fortunately, many people have become aware of this problem and are doing things about it.  There are many volunteer organizations around the coast of South America that go out to beaches and look for these oily birds.  Not only do they keep track of the species, age, sex, and number of birds coated, they also try to clean up and then release birds back into the wild.

Boersma’s research and concerned individuals around the world have also pressed government officials to make changes to shipping routes that interfere with the penguin migrations and to pass new regulations about ballast water release.  Still, the challenge continues as ships dump oil illegally, fishing vessels accidently catch birds, overfishing, global climate change, and even beach goers that may damage or disturb penguin nesting grounds.

In other locations no-fishing zones have helped penguins such as the Cape penguin (Spheniscus demersus), rebound, making it safer and easier for juvenile penguins to go in search of food.  Much effort is still needed, however.  If you live in penguin habitat, consider volunteering for penguin counts and to locate and clean oiled birds.  Support regulations supporting cleaner habitat, responsible shipping lanes, sustainable fishing, and enforcement of clean water violations.  If penguins are suffering, there are no doubt many other species facing similar problems and it’s up to us to help.

Happy Earth Day!

Posted by xdhaas on 20 April 2012
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Sunday April 22, 2012, is Earth Day, so a Happy Earth Day to you all (some people/countries celebrate this on the Spring equinox, which was in March)!  It is also the year anniversary of this blog.  I thank you all for joining me on this journey.

Each week I’ve been talking about either some of my experiences, environmental concerns, or aspects of the wildlife biologist career.  Since this is Earth Day weekend (called National Tree Day in Australia), however, I’m going to keep today’s post pretty simple.  No stories of giant bats, nothing about shrinking ice, no invasive plants lurking behind the bushes, just little things you can do to get involved.  Even little things help, and one person doing one little thing is better than nothing at all.  Go ahead and get your family and friends involved.  Make a day or a weekend out of helping out the planet.  Make it an annual event, or better yet, a monthly.  Know that while changing your lifestyle and spreading education is some of the best things to do to help, no small deed is without reward or benefit. 

For this particular weekend there’s a lot to do in many places.  All of the preserves and parks near my house are holding events and festivals, which are ranging from guided walks with a naturalist to tree planting, habitat clean ups, invasive species removal, crafts, animal exhibits, and more.  It’s a good way to get involved, check things out, get kids interested in the world around them.  Check out any local parks or preserves in your area to see what’s going on.

Many zoos, universities, and other institutes are also getting involved.  For those in the U.S. check out the link: Earth Day 2012 Event Extravaganza to see if the Center for Biological Diversity has anything listed for your area.  The Orangutan Foundation International in Los Angeles, CA, is holding a concert. 

I’ve also heard of walks and runs being scheduled, such as Kansas City’s EarthWalk 2012, which is to aid their “Bridging the Gap” program.  This program is devoted to ecological education and action in the area.  This is a good way to get people active while also aiding a worthy program.

Did you know that NASA (the United States’ National Aeronautics and Space Administration) gets involved in Earth Day too?  In Washington D.C. they are holding activities, exhibitions, and presentations on science, technology, and awareness of our planet.  There are even a few on-line activities and broadcasts non-local people can check out as well as a video contest that extends into May.

Europe is getting involved in various ways, such as festivals in Spain, green ribbons included, Greek islands are holding beach clean-ups, and some in France are holding discussions on global warming and renewable energy.

For anyone interested in taking in a movie for Earth Day, what better way than to go see the family-friendly “Chimpanzee.”  Between April 20 and April 26th, 2012 part of the proceeds will be donated to the Jane Goodall Institute’s “See ‘Chimpanzee, Save Chimpanzees” program.  This program helps preserve chimpanzee (and other animal) habitat, educate kids, and helps chimpanzee orphans.

There are lots of things you can do this Earth Day to get involved, get educated, and have fun!  My family is going to check out the movie, maybe take a hike at a local preserve and check out their activities depending on the weather, and play this cute little, printable Earth Day 2012 game.  What are you doing this Earth Day?

Battle of the Invasives

Posted by xdhaas on 13 April 2012
Posted in: Explanations, Issues. Tagged: , , , , , , , , , , , , , . 1 comment

Since we’ve been talking about invasive species lately it’s only fitting that we should then discuss what is done to both prevent them and once they’re here.  Wildlife biologists and fellow environmental workers are constantly fighting to defend the natural biome against invasion.  It’s an uphill battle.  We aren’t talking about huge invasive elephants here; those animals that come into an area tend to be small, such as insects or the larvae of animals.  Larger animals are easier to see and track and even tend to have fewer offspring in many cases.  Plants too can be invasive, their seeds easily being dispersed and hard to locate.

If caught early enough the invasive species may be able to be contained in an area, unable to escape and easier to get rid of.  Let’s face facts here.  While some biologists are just happy to control invasive, that’s usually due to the difficulty of eradicating them.  Completely removing the invasive species is generally the goal, but is hard to accomplish.  It’s rare, almost unheard of, for these species to be captured and removed from the area, sent back to their native country.  Far more likely, biologists try to prevent the spread of the species and eradicate them when possible.

I described what an invasive species is in my posts What Makes A Native 1 & 2 and Threats to Ecosystems.  Now to give a few examples just to make sure we are all on the same track.  In the United States’ Great Lake region and others there is a problem with zebra mussels (Dreissena polymorpha), which originate from Russia, and are considered the “most troublesome freshwater biofouling organism in North America” by U.S. Army Corp of Engineers due to their damage to human structures and their ability to out compete native species.  The giant hogweed (Heracleum mantegazzianum), a native to the Caucasus Mountains, can be found invading much of the U.S. and Europe.  It poses a health risk to humans and other species as it is dangerous when in contact with skin, causing burns.  Various species of termite have found their way to China.  I’m sure the trees and wooden objects in the area are less than pleased.  Possums, native to Australia and introduced to New Zealand intentionally by Europeans, have both damaged many native plants as well as killed native wildlife.  There are thousands more and they can be found almost everywhere.

Years ago no one thought anything of letting species loose in a new place.  Some were released in the hopes of creating a new hunting/trapping species in the area, some were released to “bring a touch of home” to the area.  Many others escaped their human-created confines and found themselves quite far from home.  Still others were not brought over intentionally at all but were stowaways in cargo and within the ballast water of ships.

The first line of defense is not letting invasive species into an area to begin with.  Many places now have laws controlling the intentional release of non-native species into an area.  People are encouraged to not bring certain things home after traveling abroad and to wash equipment and especially shoes before entering the country.  In New York we have a regulation preventing the transportation of firewood to and from certain places without documentation of it having been treated first.  This is to prevent the advancement of certain invasive insect species into healthy areas.  The treatment of bilge water from ships is becoming more common too.

A major problem is that these preventative methods have come about  much too late in many cases and invasive species are already here.  Wildlife and environmental professionals are often times fighting a battle against these invasive species and trying to save the ecosystem in which they are invading.

To fight the spread of invasive species, first and foremost education is very important.  State and federal, and even public and private, conservation and wildlife organizations often disperse educational signs, pamphlets, and courses about invasive species.  This is to make people aware of any laws, but also to get people involved in trying to prevent the spread of already established species from entering new areas.  This information can also inform people of what to do if they find an invasive species and any cautions that should be taken.

Some of the invasive species came to these new areas due to consumers planting them in their gardens or keeping pets that were then released or escaped into the wild, so these things are easy to prevent by simply not doing them.  Cleaning off boots, plants, waders, and water crafts after being in a certain area is also a great idea.  When I was conducting my herpetofaunal survey in the Albany Pine Bush Preserve last summer I had to sanitize my waders between each site despite the fact that they were located in the same general area.

When it comes to invasive plants many parks and preserves call on volunteers to enter the battle.  It’s a hard job, but sometimes just locating and pulling out the plants is a needed method of attack.  As long as the plants are safe to handle this is a job just about anyone can take part in.

Also, many environmental organizations and departments encourage volunteers to aid them in keeping track of invasive species of all types by reporting sightings and locations.  This allows the organizations to keep track of spread, give them a rough estimate as to density, and allow them to adapt any plans of attack they may have for the species in question.  Environmental organizations are often understaffed or with limited budget due to budgetary cuts (for some reason certain types of people find environmental work less than important) or difficulty in raising funds.  Getting volunteers involved allows more eyes to take in observations as well as spreads needed information to the public.

While herbicides and insecticides aren’t usually something environmentalists would prefer to use, sometimes these chemicals are used in controlled circumstances to fight invasive plant or insect species.  By controlled I mean that they aren’t just randomly spread all over the place, which is often done on farms, but are used in limited quantity and specific locations to minimize the damage to other plants or insects.  To do this the use of herbicides are often dispersed by hand instead of larger machines and it’s not uncommon to find professionals with packs of chemicals on their backs while they search for invasives.

Other methods to control invasive species can include putting up barriers to prevent their spread, such as fences or dams for select wildlife species.  Various traps and poisons are sometimes used to control the species as well in order to physically remove them from the area or kill them off to prevent breeding.

The public can be involved in this as well.  Just recently the state of Maryland has issued a reward  to anglers.  The state is offering a gift certificate of $200 to someone that catches the invasive northern snakehead fish (Channa argus).  Often referred to as the “fish from hell” due to its destructiveness to ecosystems and it’s dangerous ability to bite through a steel-toed boot, the state wants to do whatever it can to get rid of these fish, or at least control the population and spread.  Getting the public involved will help in both of these goals.

Anyone wanting to get involved should check out their state or federal environmental organization or a local park/preserve.  The website Invasive.org has a lot of information about invasive species of all types located in the United States.  It’s a battle that all should be involved  in.  After all, they’re invading our homes too.

What Makes A Native, Part 2

Posted by xdhaas on 6 April 2012
Posted in: Opinion. Tagged: , , , , , , , , . 1 comment

You may be wondering how any of this might apply to islands, or how species travel from mainland to island might be similar to how some non-native species travel now, which is often in the bilge water of cargo of ships.  I admit, those two comparisons do have their similarities.  There is no slow migration across land bridges onto islands.  Well, that’s not true, that was possible for some islands like I mentioned with Adam’s bridge, and likely possible for at least some of the Oceania islands, such as those that make up the Philippians and Indonesia.  But with many of the others, such as the Galapagos, chances are that’s not what happened.

In my post Island Isolation Aids Evolution I discussed a bit about how species arrive at islands.  Just as a quick re-cap, some of these methods involve birds flying to these newly exposed sites (newly exposed as water levels drop or the islands themselves rise, or newly created by volcanoes) for a rest, dropping seeds and tiny species as they land.  Some species such as reptiles may be able to survive on floating vegetation and wash up on shore, while others can just swim.  Once some vegetation springs up, migratory birds might be more likely to increase their frequency of visitation, and other birds can get blown off course in storms, sending them from their continental homes and to the direction of islands.

These arrivals weren’t quite the slow progression found on the mainland (though, this same thing can happen to the shores of continents as well), they were rather abrupt.  However, they were also probably pretty rare, and when it did happen, the number of individuals to arrive were very low.  Also, you’re not going to find a species from the middle of Russia floating on vegetation to arrive on some tropical island, either.  Any animal that swam, flew, or floated to an island probably did so from one of the closer landmasses, and as such, their climate and perhaps even some of the species in both places would be relatively similar.

This isn’t to say species that were there first wouldn’t be overrun and outcompeted by these newbies, but their arrival wasn’t determined by humans, either.  Perhaps it’s just my opinion (and it’s my blog, after all), but whether or not a species was purposefully introduced by humans (“an act of short-sighted ecological vandalism”, to quote the author of the NY Times article) or accidently introduced by carelessness, doesn’t equal the same level of introduction as more independent migration.  I mentioned some of the harm invasive species can have on their new homes here: Threats to Ecosystems

Of course, there are some species that are so common place now that most people think they are actually native to certain areas when they are not.  The house sparrow (Passer domesticus) is native to Eurasia but can be found in many parts of the Americas and are common there.  How’d they get here?  Europeans brought them over.  They also distributed them to parts of southern African, Australia, and New Zealand.  There are many more, but I offer this common bird as an example.  What you think is native may actually not be!

Back to the migrations, this land travel across bridges is how Native Americans came to the America, how Europeans arrived in Europe, how Asians arrived in Asia.  It, of course, is not how Europeans came to the Americas or Africa or Australia.  What makes someone American or European has become jumbled up now.  I was born in the United States so I’m automatically considered an American despite my largely European descent, but am I and everyone else a Native American just because we were born in the Americas?  No, I’d have to say, we are not.

The first humans arrived in the Americas around 14,000 to 12,000 years ago.  There was more than one migration, but these were the earliest people.  The skin tone of Native Americans and other general structural features are different from that of their Asian origin (there is a fairly new hypothesis that a European group may have reached the Americas before and perhaps instead of, Asians) just as Asian features are different from their Middle Eastern and before that, African features.  Within this chunk of thousands of years, humans adapted to their new homes.  Skin color is a result of melanin in the skin, which, through the process of evolution by natural selection, adapts to the climate and sun exposure levels over thousands of years.

The point is, Native Americans have adapted to the Americas.  These adaptations would have been different if they were located somewhere else, and non-existent if they hadn’t been in the Americas for quite a while.  While their initial arrival may have upset the then-current ecological balance, the small and slow migration down through the Americas gave species and ecosystems time to adapt if they could.  It wasn’t sudden.  That sounds native enough for me.

Yet, genetically there is virtually no difference between ethnicities, we are all just Homo sapiens.  So, as long as Native Americans are classified as native, shouldn’t humans in general?  I don’t really have an answer for that.  Those of European descent are obviously still adapted, even now, to a European climate, not an American one, yet these differences are really only skin deep at best.  What I do believe though, is that the culture, brought over by Europeans is not native.  It didn’t originate here.  It didn’t slowly evolve and adapt as most tribal cultures have, to the land and species.  It was thrown in rather suddenly, spread quickly, adapted as needed though I’d argue not fundamentally but only superficially, and basically crushed anything that stood in its way.  An evolution of culture could make the invasiveness of the culture, and the humans, decrease.  Humans can be invasive, but they don’t have to be.  There is a choice there.  One the nutria didn’t have.

What Makes A Native, Part 1

Posted by xdhaas on 30 March 2012
Posted in: Opinion. Tagged: , , , , , , , , , , , , . 1 comment

Last week the New York Times (<– read article here) posted an interesting opinion piece about the nutria (Myocastor coypus), a rodent native to South American that was released into the wilds of Washington State (and others) in the 1960s.  It brought up the question, how long does a species have to be in an area before its considered native?  Haven’t many species, humans included, migrated to various parts of the world?  Isn’t evolution by natural selection about adaptation and the strong surviving?  What makes a species foreign or native? 

This post is going to be about my opinion on the matter.  I’m open to my mind being changed, but support your opinions if you want to contribute!  I find this topic very interesting and certainly debatable, which of course is half the fun.

It is an interesting question, “What makes an invasive species?”  Well, it’s invasive if it’s not native and even more so if it harms the native species, right?  But what about those non-native species that don’t much bother the natives?  And where did the native species come from?  If you go back far enough, everything started in the sea, and those first semi-terrestrial species could certainly be considered non-native to the land, right?  And since all evidence currently points to Africa as the continent of human origin, humans had to migrate to all these other places.  We’ve certainly caused more than our fair share of damage and extinctions, so, by definition, humans are invasive species.  Right?  Where is the line?

Humans aren’t the only species that have gone from their point of origin to other places.  Modern horses evolved in the Americas and only entered Eurasia by migration.  However, fossils of the first known equid, Hyracotherium, can be found spread out across the entire northern hemisphere, back when North America and Europe were actually connected, though separating, landmasses.   And, of course, there is a huge debate about whether horses currently in the Americas are wild or feral, which I discussed in my recent post Wild, Tame, Feral and Domesticated.

There is a debate as to whether rabbits and hares started out in Asia or the Americas, but either way they had to migratefrom one place or the other.  Wolves, now found across both the Americas as well as Eurasia, probably started at just one point on the map.  Yet, horses are still considered native to Eurasia, wolves and rabbits are considered native to most of the places they’re found (rabbits are not considered native to Australia, as a clarification).  Again, where is the line?

Species swaps between the Americas and Asia occurred during the various periods of time there was a land bridge between what is now Alaska and Siberia, called the Bering land mass.  It’s also possible there were land bridges between other places, such as continents and islands.  How, you might ask?  During ice ages sea levels drop as the water is basically sucked up into glaciers.  A land bridge can be made out of ice connecting two areas or from exposed land.  There is a hypothesis that were was such a bridge between India and the island of Sri Lanka called Rama Setu, or Adam’s bridge.

I think, at least when it comes to continents, the vast majority of migration occurred by land.  Species don’t jump from one place to another place overnight, particularly if those locations are quite far apart.  Most of these migrations (and I’m excluding species humans brought to various places right now) were slow going.  Walking hundreds or thousands of miles takes time, after all.  It’s been estimated that even the human migration out of Africa, into the Middle East, and over to Southeast Asia only occurred at a rate of about a mile a year.  The point is, these migrations didn’t happen overnight, it was usually a slow process of species inching along.  More adaptable species, such as humans, probably moved at a faster rate than those that were more dependent on a specific type of food or habitat. 

Hordes of animals don’t come charging into new territories intent on invasion, it’s more likely a herd or pack here and there or a few individuals following the food; in other words, small, slow migrations.  Small, slow migration can allow the new area, and the species already there, some time to adapt to the invader.  They aren’t automatically overrun.  No matter how much time to adapt a species may have, sometimes they just can’t evolve fast enough and they go extinct.  This is a natural event that can happen because of a new species or because an old one evolved too fast to keep up with.  It’s nothing new.

Species introduced by humans usually occur in small numbers too, though I’ve noticed many of those species are prolific breeders.  Yet there is also no slow creeping into the area but a sudden thrust.  Less time to adapt.  Deal or die.

What about the “survival of the fittest”?  Does it matter where the species came from?  If it can outcompete the native species, doesn’t that just mean it’s better suited?  An importany point here is that it’s not just about one species, it’s about the entire ecosystem.  Species that are considered native have evolved in a way to co-exist with other species and live in a balanced community.  It is not one species dominating all the others to the point of driving them to extinction.  Maybe this happened when species first migrated, but now things are balanced again.

Yet, if such an ecological distribution did occur during or after a migration, what’s the difference between one in the past and now?  It would still cause a period of imbalance, of adaption, and of possible extinctions, right?  Right.  But did these new species arrive here by their own means?  Did they walk or fly, following food sources and habitat expansion, in a slow migration to a new home?  Or did they get brought over here by humans, rather abruptly, and thrown into the environment, giving the ecosystem and other species far less time to adapt and evolve? 

I like the nutria discussed in the New York Times article, I think they’re cute.  But I personally still think their non-native.  Maybe, just maybe, in a few hundred years or more, when they and their neighbors have balanced out and adapted to each other, they can claim the title, but right now everything is unbalanced.  These rodents haven’t decided to be rude and barge in, they were snatched from their homes and tossed over here.  It’s not their fault, to be sure, but that doesn’t affect their status of non-native.

Part 2 next week…