Novel Ecosystems and the face of the Anthropangaea

This article says it all- from the importance of genetic diversity to recognizing that sometimes landscapes with very few native species can provide real value. There is a battle brewing among the scientific community that asks,
"What will the future of forests on the human dominated Anthropangaea look like?"

Article found in Nature Magazine...
RAGAMUFFIN EARTH
A small group of ecologists is looking beyond the pristine to study the scrubby, feral
and untended. Emma Marris learns to appreciate ‘novel ecosystems’.
Joe Mascaro, a PhD student in a T-shirt and
floral print shorts, is soaking in the diversity
of the Hawaiian jungle. Above, a green canopy
blocks out most of the sky. Aerial roots
wend their way down past tropical trunks, tree
ferns and moss-covered prop roots to an understorey
of ferns and seedlings. The jungle is lush,
humid and thick with mosquitoes. It is also as
cosmopolitan as London’s Heathrow airport.
This forest on Big Island features mango
trees from India (Mangifera indica); Cecropia
obtusifolia, a tree with huge star-shaped leaves
from Mexico, Central America and Colombia;
rose apples (Syzygium jambos) from southeast
Asia; tasty strawberry guava (Psidium cattleianum)
from the threatened Atlantic coast of
Brazil; and a smattering of Queensland maples
(Flindersia brayleyana) from Australia. It also
has candlenuts (Aleurites moluccana), a species
that humans have moved around so much
that its origins have become obscure. There is
at least some native Hawaiian representation
in the form of hala, or screwpine (Pandanus
tectorius), which is pictured on the crest of
Punahou School, where US President Barack
Obama studied. There are no Hawaiian birds
here though. Mascaro sees plenty of feral pigs,
descendants of those brought by settlers from
other parts of Polynesia or from farther afield.
The soil is black and rich. Mascaro likes it here.
Most ecologists and conservationists
would describe this forest in scientific jargon
as ‘degraded’, ‘heavily invaded’ or perhaps
‘anthropogenic’. Less formally, they might
term it a ‘trash ecosystem’. After all, what is it
but a bunch of weeds, dominated by aggressive
invaders, and almost all introduced by
humans? It might as well be a city dump.
A few ecologists, however, are taking a second
look at such places, trying to see them
without the common assumption that pristine
ecosystems are ‘good’ and anything else
is ‘bad’. The non-judgemental term is ‘novel
ecosystem’. A novel ecosystem is one that has
been heavily influenced by humans but is not
under human management. A working tree
plantation doesn’t qualify; one abandoned
decades ago would. A forest dominated by
non-native species counts, like Mascaro’s
mango forest, even if humans never cut it
down, burned it or even visited it.
No one is sure how much of Earth is covered
by novel ecosystems. To help with this article,
Nature asked Erle Ellis at the University of
Maryland, Baltimore County, who produces
maps of ways that humans use Earth, to take
a stab at quantifying it. Defining novel ecosystems
as “lands without agricultural or urban
use embedded within agricultural and urban
regions”, Ellis estimates that at least 35% of the
globe is covered with them (see map, overleaf).
Their share of the planet will probably expand,
and many ecologists think that these novel ecosystems
are worthy of study and, in some cases,
protection.
For one thing, some novel ecosystems seem
to provide a habitat for native species — sometimes
crucial habitat, if all that the species originally
had is gone. They also often do a good
job of providing ‘ecosystem services’, those
things that nature does that benefit humanity,
such as filtering water in wetlands, controlling
erosion on hillsides, sequestering carbon from
the atmosphere and building soil. Provision of
ecosystem services is a popular argument for
preserving intact ecosystems, but many of its
advocates blanch a little when it comes to making
the same case for these ‘weedy’ areas.
Mascaro actually prefers novel ecosystems
to some native ones that are so vulnerable to
damage by humans that they require intense
management to maintain in their ‘pristine’
state. He sees the latter as museum-piece parks.
“Do we value the fact that nature contains a list
of things that were there 1,000 years ago, or do
we value it because it has its own processes that
are not under human control?” Mascaro asks.
For him, the value is in the processes.
Watching such processes unfold has scientific
merit to many researchers. Novel ecosystems
are often ideal natural experiments for
studying things such as community assembly
— how species find their way to a place and
which species become permanent residents
— and evolution of species in response to one
another. In essence, it takes a dynamic ecosystem
to study ecosystem dynamics, and these
novel ecosystems are the planet’s fastest movers.
Mascaro bets that all the rules of thumb and
general relationships developed over the years
by ecologists working in ‘intact’ or ‘historical’
ecosystems will probably also apply in these
new assemblages, but no one knows for sure,
because no one has studied them much.
There are some questions about the ways in
which things might be different in novel ecosystems.
Will landscape types remain the same,
with forests replacing forests and grasslands
replacing grasslands? Will novel ecosystems
evolve faster? Will they be dominated by one
species, as many who study invasive species
fear? Will species composition oscillate wildly
for decades or even longer? “We can’t know
except to observe it,” says Mascaro.
Havens of biodiversity?
One of the first researchers to see the importance
of the scrubby parts of Earth was Ariel
Lugo, a forest-service ecologist in Puerto
Rico. In 1979, Lugo was managing researchers
who were measuring the ground covered
by trees within pine plantations that were not
being actively managed. His technicians came
back to headquarters sweaty and discouraged.
“They said that they couldn’t measure the trees
without clearing all the new undergrowth,”
says Lugo. “They said it was impenetrable. I
thought they were wimps.”
The idea that ecosystems dominated by
pine, an invasive species, were so thick that his
workers couldn’t even walk through them went
against a central assumption of ecology: that
native forests will be the lushest. Millennia of
co-evolution should have created an ecosystem
in which almost every niche is filled, converting
the available energy into trees and other species
in the most efficient way. Conservationists
also generally assume that native ecosystems
contribute best to ecosystem services.
Lugo went to see for himself. Sure enough,
the pine plantations were bursting with vigour,
far more so than nearby native-only forests
of the same age. Lugo did a systematic study
of the pine plantations and some mahogany
ones, and found that the plantation understoreys
were nearly as species rich, had greater
above-ground biomass (the sheer weight of all
the living things) and used nutrients more efficiently
than the native forest understoreys. He
submitted his results to the journal Ecological
Monographs1. Reviewers were horrified. In the
end, it took almost a decade to get the paper
past peer review.
Since then, Lugo has found many novel ecosystems
in Puerto Rico and elsewhere that are
much more diverse than native forests, but that
are largely ignored by ecologists. “That diversity
doesn’t count because they are the wrong
species,” says Lugo, shaking his head. He’s
found alien trees that, by creating a shaded canopy
on parched, degraded pastureland, make
possible the establishment of native trees that
could never cope with such an environment on
their own. As a result he now finds it difficult
to despise invasive trees as he thinks his colleagues
do, and even embraces the change. “My
parents and their parents saw one Puerto Rico,”
he says, “and I am going to see another Puerto
Rico, and my children will see another.”
Lugo wasn’t the only researcher thinking
along these lines, but it was not until 2006 that
the new approach gained a manifesto — and a
name. Lugo and 17 other researchers published
a paper called “Novel ecosystems: theoretical
and management aspects of the new ecological
world order”2 suggesting that such systems were
worth scientific attention. To demonstrate the
depth of resistance to the idea, the published
paper quoted referees’ comments on the submitted
manuscript: “One reviewer commented
that the examples are ecological disasters, where
biodiversity has been decimated and ecosystem
functions are in tatters, and that ‘it is hard to
make lemonade out of these lemons’.” But Lugo
and his colleagues saw it in a different light: “We
are heading towards a situation where there are
more lemons than lemonade,” they wrote, “and
we need to recognize this and determine what
to do with the lemons.”

GLOBAL COVERAGE
The amount of land taken up by novel ecosystems, defined as unused lands
embedded within agricultural and urban landscapes.
Lemons can have their own value, says restoration
ecologist Richard Hobbs, lead author of
the paper and now at the University of Western
Australia in Crawley. Some novel ecosystems,
he says, are “alternative stable states”, relatively
entrenched ecosystems that would be very difficult
to drag back to historical conditions.
Around the time the paper came out, Mascaro
became interested in Lugo’s work and set
out to see if his results could be replicated on
the windward side of Hawaii’s Big Island. Were
the many novel ecosystems on the islands nurturing
any native species? Were they providing
ecosystem services? He studied 46 forests
growing on lava flows of varying ages at various
altitudes and dominated by a variety of species,
including albizia (Falcataria moluccana),
a fast-growing tree from southeast Asia, and
Australian ironwood (Casuarina equisetifolia).
He found that, on average, the forests had as
many species as native forests. But by and large
they weren’t incubating natives as they seemed
to in Puerto Rico3.
Part of the reason for the difference may lie in
the uniqueness of Hawaiian flora, which evolved
in isolation for up to 30 million years4. Not many
plants got to Hawaii in the first place, so competition
and predation pressures weren’t very
fierce. Without having to worry about being
eaten by anything larger than an insect, raspberries
and roses lost their thorns and mints lost
their minty defence chemicals. When people
introduced plants from other parts of the world ,
along with their attendant herbivores, Hawaiian
plants couldn’t compete.
Futuristic perspective
But Mascaro’s results didn’t put
him off the novel-ecosystem
concept. For one, he found
that in many measures of forest
productivity, such as nutrient
cycling and biomass, novel forests
matched or out-produced
the native forests. They might
not be ‘natural’ in the eyes of
purists, but they are behaving
exactly as they should . “These
ecosystems, like it or not, are
going to be driving most of
the natural processes on Earth,” he said at the
2008 Ecological Society of America meeting
in Milwaukee, Wisconsin. It’s a message that
Peter Kareiva, chief scientist at the Nature Conservancy
in Seattle, Washington, wants to see
move from the academic world to the world
of conservation management. “You hear conservationists
talk about what they want to save,
what they want to stop,” he says. “They should
talk about what they want the world to look like
in 50 years.” Studies of novel ecosystems could
help conservationists to “face the facts and be
strategic”, Kareiva says, rather than trying to
beat back the unceasing tide of change.
Kareiva is a great fan of the ecosystem-services
argument for preserving nature. But he
admits that the problem of what to do when
novel ecosystems provide better services than
the native ones is “a question we don’t talk
about that much”. Nevertheless, he is willing to
imagine a world in which, for example, exotic
strains of the reed Phragmites are allowed to
thrive in US wetlands because they provide a
great habitat for birds, rather
than be torn out in an expensive
and potentially fruitless attempt
to return native vegetation to
dominance.
Ecosystem-service arguments
are powerful enough to
get some ecologists to abandon,
or at least put to one side, their
deep distrust of novel ecosystems.
Like many of his peers,
Shahid Naeem, an ecologist at
Columbia University in New
York, says he “would love to get rid of every
invasive species on the planet and put all the
native species back in their place”. Yet he’s willing
to see what can be made of novel ecosystems
as he feels an imperative to improve conditions
for the billions of humans on Earth.
The idea that novel ecosystems provide
welcome diversity has also gained traction.
Thinking on ‘invasive species’ has mellowed
significantly since the field was first established
in the 1950s. Newer work by the likes of Mark
Davis at Macalester College in Saint Paul,
Minnesota, and Dov Sax at Brown University
in Providence, Rhode Island, has shown that
the vast majority of species that humans move
around can slot into new ecosystems without
driving anything else extinct, and that the common
vision of invasive plants forming dense
monocultural stands that take over everything
else in their path is actually the exception. Yet
the newcomers in novel systems can still be a
genuine worry.
Peter Vitousek, an expert on Hawaiian
biodiversity at Stanford University in California,
would put albizia forests in the category
of dangerous invaders, because they wipe out
stands of the native ‘ōhi‘a tree (Metrosideros
polymorpha). He acknowledges the services
that novel ecosystems provide and that “they
may even support native biological diversity in
some important circumstances”. But, he adds,
“as with many good ideas, [tolerance of novel
ecosystems] can be taken to an extreme at which
it is no longer useful. I think most of the albizia-
dominated stands of Hawaii represent that
extreme.” His point is well illustrated where one
of Mascaro’s albizia forests abuts a native ‘ōhi‘a
forest. The albizia trees on the boundary actually
lean out towards the ‘ōhi‘a — growing sideways
to escape the shade of the next row in, encroaching
on the natives’ sunlight and looking poised
to usurp them. It is a menacing spectacle, and an
apt symbol for their tireless expansion.
Mascaro grants the point. “I can understand
where a manager wants to bulldoze an
albizia forest if they are worried that it is going
to exterminate an ecosystem type that is the
last on Earth,” he says. “If we want to debate
whether to use or conserve novel ecosystems,
we will always have to deal with the risk they
pose to other systems. But at the moment, we’re
scarcely debating it at all.”
Novel ecosystems are likely to cause at least
some extinctions. For example, species that
have evolved dependent relationships with
other species are less likely to do well in a world
in which the pot is stirred and everything is
redistributed. Hawaiian honeycreepers, beautiful
birds that often feed only on one type of
flower, are not doing well; several are already
extinct. So for those who care about slowing
or stopping the rate of such extinctions, novel
ecosystems are a net negative .
James Gibbs, an ecologist at the State
University of New York in Syracuse, subscribes
to this view. “I think celebrating [novel ecosystems]
as equivalent or improved is not appropriate.”
As an example, he points to Clear Lake
in Northern California, where the number of
fish species has risen from 12 to 25 since 1800.
Sounds like a success story. But, says Gibbs,
species that were found only in that lake were
replaced with fish that are common elsewhere
— so there was a net loss in biodiversity. A similar
caveat may hold for the genetic diversity
hidden within a species. Forests dominated by
the offspring of a handful of exotic colonizers
could be less genetically diverse than forests
that have sat there for thousands of years.
A question of values
In the end, the question of novel ecosystems,
like so many questions in ecology and conservation,
boils down to what
should be valued most in
nature. For people who value
processes, such as Mascaro,
novel ecosystems are great
hubs of active evolution. For
those who value ecosystem
services, any novel ecosystem
could be better or worse than
what came before depending on
how it operates. For those who
care about global extinctions or about preserving
historical ecosystems, they are bad news.
Gibbs says he values the exquisite complexity
of ecosystems that have evolved together over
thousands or millions of years. “Why are we
worried about the extinction of languages, the
roots of music, all these weird cuisines?” he
asks. “There is something about diversity and
our need to steward it. It is the subtlety and the
nuance and complexity that makes life interesting.”
Novel ecosystems seem, to him, to lack
this value, to be samey and artificial, “sort of
like eating at McDonalds” .
To Kareiva, though, that attitude is “one of
the reasons the conservation movement is failing.
To think there is some kind of garden of
Eden pristine ecosystem. There is none! That
view is just going to get us nowhere.”
Indeed, the Garden of Eden view, in which
ecosystems are static, is no longer widely held.
Th is means that novel ecosystems, far from
being a new phenomenon, simply represent
the latest changes on a dynamic Earth. Gradual
climatic changes and sheer randomness mean
that some species wander around continents
over vast timescales, fleeing glaciers, splitting
up and reforming . This is why Davis and some
others do not like the ‘novel’ label. “Ecosystems
are always new, from one year to the next,” says
Davis. “Ecosystems are always encountering
new species — it might be not
from another country but from
100 metres upstream. Much
more accurate would be to refer
to these as ‘rapidly changing’
ecosystems — but I guess that
is not catchy enough.”
Standing in his Hawaiian
forest, Mascaro is all too aware
of change — and it is something
he values, even if humans did
have a hand in the process. He never swore allegiance
to preserving ecosystems as they were
before humans arrived, as many conservationists
of an older generation did. “People come
up to me and say ‘it sounds like you’ve given
up,’” says Mascaro. “I want to say ‘I never took
up arms, my man’. This isn’t about conceding
defeat; it is about a new approach.” ■
Emma Marris writes for Nature from
Columbia, Missouri.
1. Lugo, A. Ecol. Monogr. 62, 2–41 (1992).
2. Hobbs, R. J. et al. Global Ecol. Biogeogr. 15, 1–7 (2006).
3. Mascaro, J., Becklund, K. K., Hughes, R. F. & Schnitzer, S. A.
Forest Ecol. Manage/ 256, 593–606 (2008).
4. Ziegler, A. Hawaiian Natural History, Ecology and Evolution
157 (University of Hawaii Press, 2002).
See Editorial, page 435.
“There is no garden
of Eden pristine
ecosystem. That
view is just going to
get us nowhere.”

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NEWS FEATURE NATURE|23 © 2009 Macmillan Publishers Limited. All rights reserved
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Translational Ecology

It's difficult to define oneself in any field, but sometimes I find it especially hard to define myself, as I wear a number of different hats in my work.  Landscape designers don't conduct ecological surveys, and ecologists aren't called upon to draft construction documents.  Good to know I'm not the only one who is working to build a bridge between the gulf that separates science and action.

William H. Schlesinger from Science Magazine in this week's edition writes:
"Ecology is well into its second century as an organized scientific discipline, rich with observations, experiments, and a general understanding of how the natural world works. Today's environmental scientists have a powerful array of tools and techniques to measure and monitor the environment and to interpret vast and diverse data. Yet despite producing an enormous amount of new information, ecologists are often unable to convey knowledge effectively to the public and to policy-makers. Unless the discoveries of ecological science are rapidly translated into meaningful actions, they will remain quietly archived while the biosphere degrades.
Global warming, the Gulf of Mexico oil disaster, invasive species—these are but a few of the issues concerning environmental scientists and, increasingly, the public. What is needed is a new partnership between scientists and advocacy groups that conveys ecological information accurately and in ways that stakeholders (including policy-makers, resource managers, public health officials, and the general public) can understand. Just as physicians use "translational medicine" to connect the patient to new basic research, "translational ecology" should connect end-users of environmental science to the field research carried out by scientists who study the basis of environmental problems. Translational ecology requires constant two-way communication between stakeholders and scientists. It should continually alert scientists to aspects of the environment in need of study to produce new data, while clearly synthesizing what is already known from field studies and its relevance to policy. The partnership's purpose should be to ensure that all stakeholders know the implications of scientific discoveries and understand their impact on alternative ecological diagnoses.

CREDIT: GETTY IMAGES/ISTOCKPHOTO

Good examples of translational ecology involve interdisciplinary teams of scientists, engineers, public health experts, and members of the end-user community. A recent study of the environmental impacts of mountain-top–removal mining involved a collaboration between ecologists and public health experts.^* Earth Justice and other nonprofit groups used this material to convince the U.S. Environmental Protection Agency (EPA) to issue new guidelines that will severely limit most such mining practices. In earlier years, research by wetland ecologists helped the EPA outline how to recognize and delineate wetlands, based on soil characteristics. Other scientists are now working with advocacy groups to help policy-makers understand the implications of human perturbations of the global nitrogen cycle. And we can be sure that scientific analysis of the impacts of deep-water petroleum extraction will also be forthcoming—in this case, unfortunately, as a retrospective.
Translational medicine grew from the recognition that basic research findings were not moving effectively into the development of drugs and treatments. To overcome this problem, in 2006 the U.S. National Institutes of Health established a Consortium for Transforming Clinical and Translational Research, which grants Clinical and Translational Science Awards. These awards have recently been increased to over $250 million for the next 5 years, expanding the consortium to 55 institutions nationwide. Translational ecology should similarly connect the end-users of environmental science with the major funders of environmental research.
This week, the Ecological Society of America concludes its annual meeting in Pittsburgh. The world's largest international organization of ecologists can play a critical role in spurring translational ecology. It has drawn together more than 3000 scientists, policy-makers, and citizens to explore the causes and consequences of this year's theme, global warming. Many of the sessions call for ecologists to take charge and improve science education and literacy, so that issues related to global warming are not misunderstood. Connecting ecology to stakeholders in these and other ways should enhance the understanding and application of ecological concepts, ensuring that scientific rigor is brought to bear on the world's many environmental challenges."

Original story at Science HERE
William H. Schlesinger is president of the Cary Institute of Ecosystem Studies in Millbrook, NY. 

Sudden Oak Death is Spreading into our National Parks

One of my clients, Dave Deppen, tipped me off to this article a few days ago. For those of you folks out there who haven't yet heard about Sudden Oak Death (SODs), this is a good place to start learning.
Point Reyes National Seashore is a 71,000-acre preserve on a peninsula that juts out from the San Andreas fault, the western-most tip of the lower 48 states. This spot is a favorite destination for whale watchers, bird lovers, and hikers. Unfortunately, these same visitors are inadvertently spreading a deadly fungal disease into pristine oak forests, on the bottoms of their shoes. So far the park has seen a 75% mortality rate in tan oak forests, the most susceptible to SODs. Park officials warn that the loss of these oaks has far reaching effects, from reduced habitat for animals to increased fire risk. One solution is to close the park during wet winter months when the disease is most likely to spread, according to researchers.
Sudden oak death was first discovered in Mill Valley in 1995, reportedly through infected nursery stock from Europe. SODs is a fungus that oaks of Europe are resistant to, but the genetics of our American live oaks are of a different enough lineage that it has proven fatal. Since its discovery, the disease has spread to 14 California counties, a few in Oregon and California, and cases have been reported in other states as far as the midwest. As of yet there is no known cure for the disease.
There are simple things we can all do to help prevent the spread of SODs, most importantly by not introducing it on our hikes. Shoes, tools, tires, and anything else that come into contact with the soil can and should be disinfected before travelling to a new place. Being careful not to transport infected wood is important. Also, being sure to buy plants from reputable nurseries that have passed inspection can prevent you from bringing it home to your own garden. Remember, plant material and soil are vectors for the disease, and there are many carriers of the disease, including a long list of native plants.

For starters, check out the Marin IJ article here
Then, if you'd like to know more, go to the Wikipedia site, with photos and links to more sites, including host plant lists and maps.

How Much is a Tree Worth?

As an ecologist I never thought I'd be in such high demand!
Today while perusing my blogs I found this short piece on Costa Rica and their new program to reduce their carbon emissions to zero by the year 2021. An ambitious plan for a country that has lost more than a dozen amphibians due to habitat loss.
Costa Rica is a land known for its natural beauty, rainforests, and 5% of the world's species. Ecotourism is one of the leading industries in this tiny country, but one must not forget that the main economic force guiding this country is agriculture.
According to the article in Treehugger, "Just days ago, Costa Rican President Oscar Arias planted the 5 millionth tree of the year near his office in the capital San Jose...By the end of 2007, Costa Rica will have planted nearly 6.5 million trees, which should absorb 111,000 tonnes of carbon dioxide a year."
While this may be a wonderful idea, one must ask: What kind of trees are they planting, and how could they possibly take place of all the trees felled each year to make way for soybeans and other crops?
"Costa Rica is facing a wood shortage and must now import wood from other countries to meet domestic demand. And currently, there are no incentives for allowing abandoned agricultural land to regrow naturally into forest, so farmers are either shifting their agricultural land use to or planting native or exotic tree species for reforestation incentives," according to rainforest advocates at mongabay.com
And just how much carbon can a new tree absorb in comparison to a mature forest? The EPA, who I trust as the right arm of the Bush administration (yes there is some sarcasm here), claims, " Carbon sequestration rates vary by tree species, soil type, regional climate, topography and management practice. In the U.S., fairly well-established values for carbon sequestration rates are available for most tree species. Soil carbon sequestration rates vary by soil type and cropping practice and are less well documented but information and research in this area is growing rapidly. Pine plantations in the Southeast (US) can accumulate almost 100 metric tons of carbon per acre after 90 years, (Do we have 90 more years?) or roughly one metric ton of carbon per acre per year," and they go as far as to say that carbon sequestration capabilities are reduced as a forest matures, as if to say plantations are better than natural forests. Costa Rica and the US aren't the only countries with faulty logic.

Officials from the Indonesian ministry of agriculture and the palm oil industry have been touting that palm plantations sequester more carbon than native rainforests. Not so, according to Mongabay.
" As is the case with any plant, oil palm trees do sequester carbon sequester carbon as they grow -- carbon is a basic building block of plant tissue. Nevertheless, the process of clearing forest in order to establish a plantation releases more carbon than will be sequestered by the growing oil palms. So while a new oil palm plantation may grow faster -- and sequester carbon at a higher annual rate -- than a naturally regenerating forest, in the end the oil plantation will still store less carbon (50-90 percent less over 20 years) than the original forest cover."

Not to mention that fact that these trees planted will not match the loss of habitat due to clear cutting of the rainforests.
Nice try, Costa Rica, but you still have a long way to go, including fair analysis of the full range of ecosystem services an intact forest provides- from clean air and water, to biodiversity and products from the forest. How much is a tree really worth?

For the abbreviated article on Costa Rica in TreeHugger

Fish Populations Controlled by Sex Changes

Florida has been inundated with invasive species. Since the 60's, Florida's rivers have been slowly filling with an Aquatic plants called Hydrilla. To combat the invader, Tilapia fish were brought in, along with two species of snail. Unfortunately, these exotics preferred the native species of vegetation over the Hydrilla, sending the biodiversity of Florida's rivers into further turmoil.
Now Juan Gutierrez, a bio-mathematician at Florida State University, thinks he can solve the problem. Gutierrez has developed a mathematical model of a population in which males carry two different sex chromosomes (XY) and females are XX. Unlike humans, the sex of a fish can be changed by exposure to different sex hormones. According to this week's Nature,
"By exposing genetic males to female hormones, or vice versa, it is therefore possible to create a male that is genetically XX, or a female that is XY or even YY. Such individuals, with the genetics of one sex but the physical characteristics of the other, are referred to as carriers of 'Trojan sex chromosomes'."
After simulated generations with the model, it was shown that when there was an introduction of YY females, the subsequent offspring were predominantly male, and that this male dominance only strenghtened with each new cycle. Eventually there were only males left in the population.
Gutierrez stresses that this only a model, and further study will have to be made to determine if this technique would truly work in a real environment. However, the potential could be the final solution to the problem, as this is not introducing genetically modified organsims or new potentially invasive exotics into the rivers.
I wonder if any thought has been given to whether introducing these altered fish runs the risk of increasing their fertility rates and creating a population explosion.
For the article in its entirety in news@Nature

The Latest Online Interactive Craze

I stumbled on this old article today from April, but I think many of you would still find the info relevant. Craig Newman of Craiglsist and researchers at the University of California at Berkeley and Texas A&M have developed a technology in hopes of attracting gamers and nature- enthusiasts, one in a series of webcam projects planned around the globe. Craig has set up a webcam from his window out to Sutro Forest in San Francisco. Users can operate the camera to watch for birds. They're hoping that online viewers will help him spot the elusive Ivory Billed Woodpecker, and that in the future other web cam projects will help conservation efforts and allow people to view nature from their homes.
I found this post while trying to sync my iPhone browsers to my laptop. Remote control webcams, laptops, and iPhones, desk-surfing wildlife videos- what next?
Wired Article

Animals are Invading Our Cities!

Last night I read a cute article in the NY Times about animals loose in Manhattan. First, a hawk fledgling made its way from nest to city streets. A couple of hours later, a young kestrel fell from the nest. Later, a sheep was sighted roaming the streets.
A sheep? Well, that's hardly a wild animal, so we'll just say she escaped the meat market and was rescued and named.
But the birds of prey are of great interest. Last spring when I visited Central Park there were t-shirts and a bird cam featuring a nesting pair of peregrine falcons on a high-rise apartment building overlooking the park. It seems that areas of high human density are also home to the pigeons, sparrows, and rats that these winged predators hunt for food.
These predatory animals aren't alone in their ability to live near human dwellings, even seek them out. Last night I walked through the shipping district of my neighborhood in Sausalito, 3 miles North of San Francisco across the Golden Gate Bridge. It was just getting dark when I spotted my coyote friend. A coyote, in Sausalito? Yes, indeed. Last time I saw it I thought it must be lost. But this time I followed it from a distance, and watched it slink through the gaps in fences like a kid in its own neighborhood.
Herons are other predators that seem to thrive here along the Bay, despite the industry and human density. Both the coyotes and the herons are here because they eat the small animals that in turn live here because of humans. Coyotes are known to eat rodents, cats and even small dogs if the opportunity strikes them. Herons love the rats, and have been known to eat small kittens and anything else that will fit down their throats.
And so another food web has already begun, right under our urban noses.
Who says you have to leave the city to find wildlife?
for the article in NY Times

Genetic Tests Reveal Asexual Reproduction in Animals

Scientists have confirmed that a shark kept in captivity did indeed produce an offspring in 2001 without the fertilization from a male. Officials at the zoo were hesitant to announce the discovery until they'd confirmed that the birth was through parthenogenesis, rather than through sexual reproduction.
This discovery is important to the conservation of sharks, and could prove a double-edged sword for the declining family of cartilaginous fishes. Parthenogenesis could potentially weaken genetic diversity and make sharks more susceptible to diseases. Should shark numbers continue to fall, this asexual reproduction could essentially keep them from further evolving to survive their conditions. However, some scientists believe this was very common in early animals whose survival depended upon being able to reproduce when numbers were not large enough, as when an animals gets separated from others in an isolated area.
Other animals to have recently surprised us with their ability to reproduce without sex are komodo dragons, with two confirmed cases last year at separate zoos.
This form of reproduction has recently been a suggestion as to what happened with honey bees mysteriously disappearing, as drones of a colony are clones of the queen, giving them less resistance to diseases.


for BBC article on sharks
for BBC article on Komodo dragons

Cheetahs Cheat for Diversity

A study by the Serengeti Cheetah Project has shown that female cheetahs mate with different fathers. This poses a serious threat to females due to the increase exposure to diseases, while making them more vulnerable to predation because of the long distances they must travel to find males. However, the fact that nearly half of their litters are fathered by multiple males is great news in that it increases their chance of survival through genetic diversity.
Cheetahs are declining in numbers, and adult population is estimated at 10,000.
for full story at inthenews

Forest Fire on Catalina Stirs the Embers of Controversy

Along the southern coast of California are a chain of little islands that make up the Channel islands. The most popular of these is Santa Catalina, better known as just Catalina. It is a favorite spot for the vacation get away, and the main tourist destination is the town of Avalon.
Vacationers this week got more than they bargained for when a wildfire engulfed most of the island and drove evacuees from their hotels. The blaze was contained by Friday, and only one house and six businesses were damaged.
Scientists are sitting on the edge of their seats right now, as this fire will surely bring the decade battle over the restoration of native plants species to a head.

Historically, the Channel Islands were isolated from the mainland and had no large foraging animals on them. Unique plant species seen nowhere else in the world were found there, and in turn supported unique animal species such as the Catalina fox and the Catalina Orangetip butterfly. As people started to inhabit the islands, they brought with them bison, pigs, and goats. These animals decimated the ecosystems of the islands, and put its native animals at risk. Over the years, efforts to remove the introduced foragers were met with strong opposition from animal right advocates, who opposed killing the animals. Science has gradually won over, and now on the island the only remaining threat to plants are the bison, which are managed by the conservancy department on Catalina.
The crucial moment is now here, when the power of fire has the potential to awaken the dormant seeds of plants whose adult populations have been long extinct. This could bring new life to the island, and restore the precious habitat. A fire in 1999 had a similar effect on plants, but new seedlings were decimated by the roaming buffalo. Scientists worry that this awakening could have the effect of wiping out the potential for reintroduction if this happens again.
"If it springs back and is eaten, its going to be gone forever."

to learn more about conservation efforts on Catalina
for more info on Catalina, including the latest fire go to the Wiki site
for the LA times article on the native plant story