Why is biodiversity important to human well-being?

Teatown member Margaret Lloyd recently reminded me, “It is all about the connections!”  She should know, it was Margaret’s uncle, John Storer, who in his 1953 book The Web of Life made the case for how all living things from bacteria to people fit into a pattern of life that depend upon each other and the physical world around them for their existence. Yet, more than 50 years after the book’s publication, most people still don’t get it: people are connected to the physical and natural systems that makes life on Earth possible. We are intimately linked to all nature’s species and our summed actions matter by affecting the whole.

Environmental educators in recent decades answered the question of why biodiversity is important to humans by discussing quality of life issues like scenic beauty and outdoor recreation. Since the 1970’s, conservation biologists similarly focused on creating new parks for our enjoyment and saving charismatic endangered species like Bald Eagles and Florida Manatees. These are certainly worthy endeavors, but in recent years a shift has occurred among scientists and a few policy analysts as to why we should value other species and protect them.

Scientists now understand that biodiversity is key to human well-being for its role in ecosystems and its essential links to human health. An ecosystem is a network of biodiversity and non-living elements that interact to produce benefits essential for the on-going workings of the system. These benefits are called “ecosystem services.” Earth consists of a mosaic of ecosystems – e.g. forests, grasslands, wetlands, streams, estuaries, and oceans – whose services provide materials and processes that sustain life. Ecosystem services can be divided into four categories: provisioning services, regulating services, supporting services, and cultural services. It is these services that enable our communities and economies to prosper, and provide the foundation for our well-being.

Ecosystem Services (adapted from Chivian, E. and Bernstein, A. 2008. Sustaining Life: How Human Health Depends on Biodiversity. Oxford University Press, New York).

The economic value of ecosystem services is greatly underappreciate. A 2008 study commissioned by the European Union concluded that the global economy is losing more money from the disappearance of forests than from the banking crisis. The annual cost of forest loss is between $2 trillion and $5 trillion! This calculation comes from adding the value of forest services such as providing clean water, preventing soil erosion, and absorbing carbon dioxide. The point is that as forests decline nature stops providing services, and the human economy either has to provide them at great cost or do without.

In the last two decades, ecologists and physicians working together have discovered a strong relationship between healthy ecosystems and healthy people. Especially important are recent discoveries that reveal how biodiversity helps moderate or prevent infectious disease outbreaks. Lyme’s Disease, for example, is reduced in areas that have a high diversity of small mammals. This association is called the “biodiversity dilution effect” – as the disease causing organism is diluting by being spread among a diversity of small mammal species. It also is worth remembering that many medicines come from nature, and that biomedical research depends on many kinds of animals and microbes, a number of which regrettably are threatened with extinction.

The take home lesson is that it is clear that our health and human well-being depends on biodiversity and functioning ecosystems. Do you know of other connections between biodiversity and human well-being?  If so, post a comment!

Cheers,

Fred

White-nose Syndrome Arrives in Putnam County

In February 2006, a caver visiting a cave near Albany, New York, photographed several hibernating bats with an unusual white substance encircling their noses. The same caver also noticed several dead bats lying on the cave floor. By the winter of 2007, the New York Department of Environmental Conservation began receiving reports from the area west of Albany of bats uncharacteristically flying during winter days; sick bats with white noses; and dead bats in several caves.

These  bat deaths would prove to be the beginning of what appears to be a deadly epidemic for bats and an ecological disaster for the northeastern United States, and perhaps, beyond. In 2008 and 2009, hundreds of thousands of hibernating bats with white noses have died in caves and mines from Vermont to Virginia. New locations in 2009 included Fahnestock  State Park in Putnam County, New York. So, “white-nose syndrome” has come to our Hudson Hills and Highlands bats.  Will we see less bats this year?  What will be the affects to our region? 

Some biologists estimate a two-year population lost of up to 75% for some species of northeastern cave bats (e.g. little brown and big brown bats). At most risk is the already endangered Indiana bat. Often the infected bats are low in body weigh and fat. In some caves or mines, 90 to 100 percent of the bats have been found dead.

Biologists from nonprofit, state and federal agencies are  trying to find the cause of this deadly mystery. Recent identification of a previously undescribed cold-loving fungus (of the Genus Geomyces) is the cause of the white noses – but it is unclear if this is an emerging fungal pathogen disease or if the fungus is a consequence of sick bats weakened from some other causal agent. Some biologist suggest declining number of food insects from misuse of pesticides causes the bats to enter hibernation with insufficient fat stores.  Others wonder if climate change has changed the energetics inside caves. 

If the fungus is an “emerging disease” (a disease new to an area, often transported by people form one area of the world to another where native animals/plants have no evolved defenses), the situation would be similar to the chytrid fungus skin infections that has been implicated in the death and extinctions of a rising number of amphibians.  Why are such emerging diseases on the rise?

New York is home for nine species of bats. Six of these species hibernate in caves and mines in the winter months – and consequently are at risk of the white-nose syndrome. Bats are misunderstood creatures. To the informed they are known to be beneficial to our environment and ecological health. They are the only mammal that can fly, and our New York bats are insect-eating machines, performing incredible aerial acrobatics as they chase and catch up to 50% of their weight in insects each night. Their economic value in devouring insects is worth millions of dollars each year to the agricultural community and to our outdoor comfort.

To see photos and maps, visit the USGS National Wildlife Health Center White-nose Syndrome Webpage.  You can follow this website to learn how scientists are working together in hope of  finding a solution to this wildlife crisis. It is a veterinary medicine detective story.

If you see any unusual bat behavior in our area — for example, dying bats on the ground (do not touch them, as bats can carry rabies)  or note an unusual absence of bats in your own backyard this summer — please post a comment to this post.

Posted by Fred Koontz

Living in the Midst of a Predator

Teatown has released a report “Coyotes of the Hudson Hills and Highlands” detailing results of a 2007-2008 study (download the full report here). This effort sought to increase our understanding of coyote behavior and ecology, so as to minimize coyote-human conflict.

Historically, coyotes were not found in the Hudson Hills and Highlands. At the time of European settlement, their geographic range was restricted to the mid-west prairie states. Over the last 100 years, however, coyotes have successfully colonized the entire lower 48 states. Eastern colonization began in the early 1940’s in western New York, southern Canada, and Maine. Coyotes moved into the Hudson Valley about 1960 and into the Hudson Hills and Highlands about 1975. About 10 years ago, human-coyote conflicts began to be reported, typically involving predated pets or perceived threats to public safety. Every indication is that coyote numbers are increasing throughout the Hudson Valley and New York (about 30,000 coyotes currently live in New York).

Methods. Located in the heart of the Hudson Hills and Highlands, the project’s study site, Teatown Lake Reservation, typifies much of the region. To understand where coyotes are likely to be encountered by people, “camera trap surveys” of free-ranging coyotes were conducted throughout the Reservation between May 2007 and June 2008. Attached to a tree at a height of about 24 inches, the cameras automatically detected and photographed warm-blooded mammals and birds passing within 25-40 feet of the unit. Six rounds of surveys deploying cameras at 97 locations were conducted, resulting in 41,544 hours of sampling.

Results. 1,223 animals were identified in photographs, including: white-tailed deer, gray squirrels, common raccoons, coyotes, turkeys, red foxes, Virginia opossums, striped skunks, North American otters, fishers, domestic dogs, and people. No long-tailed weasels, bobcat, or gray fox were detected despite being known from the area. Chipmunks and rodents probably are too small to be seen on the photographs, and might account for some of the 275 “blank” photos. Table 1 summarizes the results of the study.     

 Table 1.  Animals photographed by camera trap surveys at Teatown Lake Reservation.

Round	Deer	Squirrel	Raccoon	Coyote	Turkey	Red Fox	Opossum	Others	No ID	Total
1:  “A”	294	8	6	9	3	2	2	19	104	447
2:  “B”	80	21	7	8	1	1	0	13	17	148
3:  “C”	262	35	9	9	9	2	0	19	57	402
4:  “D”	112	11	5	2	0	3	4	22	16	175
5:  “E”	96	17	8	4	7	2	3	9	53	199
6:  “F”	65	18	7	4	3	2	0	0	28	127
Totals:	909	110	42	36	23	12	9	82	275	1498
% of Animal Photos	74.3	9.0	3.4	2.9	1.9	1.0	0.7	6.7	—-	—-

 

The 36 photographed coyotes could not be distinguished as individuals. However, because of differences in tail length and other physical markings, we suspect at least 6-10 different coyotes were observed. Three of the animals were first-year pups. There were no significant seasonal differences in the number of coyote photographs, but we did see a trend for the fewest coyotes in November and December. The 36 photographed coyotes were observed at 21 of the 97 (21.6%)  camera locations.  The habitat for each of the 21 locations was recorded. All 36 coyotes were photographed at night.  Teatown Lake Reservation contains five major habitat types that typically are found in the Hudson Hills and Highlands. Coyotes were found more often than expected in scrubland, meadows,  and forested hardwood swamps.

Conclusions. Camera trap technology proved useful for wildlife managers at Teatown to better understand coyote ecology and behavior, and we learned that:

 1. Camera trapping methodology is especially practical at small geographic scales (500 to 5,000 acres) and allows wildlife managers to make specific recommendations aimed at minimizing coyote-human conflict at their site.

 2. Coyotes at Teatown, and we infer throughout the Hudson Hills and Highlands, can be found anywhere but are most likely to be encountered by people when they visit natural areas of shrublands, meadows, and forested hardwood swamps during the daytime and startle the resting coyotes — especially when these habitats also are away from human-use areas. Of course, traveling in these habitats at twilight or at night when coyotes are most active increases the chances of encountering them. We suspect that these generalizations hold for resident coyotes, but that dispersing juveniles or transient adults might be encountered anywhere, including near houses, schools, businesses, and (especially) farms.

 3. While the coyotes photographed in this study were relatively low in number (36), the 3-7 adult individuals were more than we expected for the land area surveyed (1-2 were expected, based on often reported densities of 0.5 coyotes per square mile in New York). We conclude that there are many more coyotes in the 936-square mile Hudson Hills and Highlands than is generally believed; we estimate at least 550-750 in the region.

Recommendations. Based on these observations and other known facts about eastern coyotes, we offer the following suggestions to minimize human-coyote conflict in the Hudson Hills and Highlands:

 1. Do not feed coyotes or encourage them to enter yards or human-use areas by carelessly storing garbage. Be sure to feed all pets inside and do not allow pets to run free. Supply only enough birdseed to feeders that can be consumed during daylight hours; excess birdseed draws rats and other rodents that, in turn, attracts coyotes.

 2. Coyotes natural inclination is to avoid people. They can be found anywhere in our region – day or night, but usually at night. If you do encounter one, especially near human-use areas, be aggressive in your behavior – make loud noises, wave your arms, throw sticks and stones.

 3. Understand that coyotes prefer the cover and remoteness that shrublands, meadows, and forested hardwood swamps provide. Be especially careful when walking in these areas.  Remove brush and tall grass from around your property.

 4. Understand that coyotes are “dogs” (canids) and perceive small dogs and cats as food, and treat larger dogs as competitors. This is especially important from February to June, when coyotes are breeding and denning with pups and become especially territorial.  You should always keep pet dogs on leashes when you hike or walk in parks and other natural areas. You should not travel with dogs in the more remote parks and natural areas between February and June.

 5. Be especially ready to encounter dispersing juveniles in unexpected places (e.g. in more human-use areas) in February and March when parents force them out before breeding season begins.

 6. Teach children to appreciate coyotes from a distance and inform them how to respond if they do encounter a wild animal.

 7. If you live adjacent or near a park, nature reserve, or other protected land your cooperation with the steps above is essential.

 8. Ask your neighbors to follow all the steps above.

Acknowledgments. The project team consisted of Fred Koontz, Mike Rubbo, Charles Koontz, Susan Elbin, and Alex Cochran. Teatown Lake Reservation thanks Wildlife Trust for financial support of the project.

Primary References.   1) Gompper, M. E. 2002. The ecology of northeast coyotes: current knowledge and priorities for future research.  Wildlife Conservation Society, Working Paper No. 17. Bronx, New York.  47 pp.   2) Parker, Gerry. 1995.  Eastern coyote: the story of its success. Nimbus Publishing, Halifax, Canada. 254 pp.

 Posted by Fred Koontz