In the January 2010 issue of Bay Nature there is an article entitled “Worth the Wait” that discusses the eventual  demise of the open land incorporated within the Concord Naval Weapons Station.  Perhaps the news is not completely dismal as the author does point out that the City of Concord is moving towards a plan that melds development and greenbelts  to avoid complete congestion. Simultaneously,  the East Bay Regional Park District and East Bayers are supporting the creation of a park and restoration of at least 2,500 acres. But with the land still under the control of the Feds, environmental reviews in progress, and plans still under debate, the future of these rolling hills and grasslands are up in the air.

You may have noticed I said that “perhaps the news is not completely dismal” but being total honest I don’t see a great ending to this saga, but instead see a ending in which residents claim it could have been worse.  Yet in another instance of developers ruling the world and City Councils bowing to incoming dollars, an impressive ecosystem will most definitely fall with the sound of grading.  And shame on me for thinking that the former Naval Weapons Station could be removed and blended into the rest of the landscape as if time had moved counterclockwise for 65 years. 

But when quotes like the following from developers and cities surface, I can only drop my head as the value of the “last parcel” is not in the parcel for what it is, but what we can do to it.

The city council seemed to see the land as a blank slate, a void to fill in with more Concord: the same pleasant suburbia, supersized. Prominent area home builder Albert Seeno Jr. observed, “It’s next to major freeways, adjacent to a BART station. It’s an infill project. It’s flat. It’s ideal. I grew up in Concord. It would be nice to build the last available parcel.”  Bay Nature, Jan 2010, by John Hart

Is the notion of a Federally Protected Open Space sheer idealism? 

Apparently it is indeed.  And even worse is that I will eventually placate myself into uttering those damn words that we have been forced to say untold times before as vital habitats become urbanized landscapes battling wildlife that have the nerve to infiltrate our world.  “I’m glad they left a few fragmented greenbelts.  It could have been worse.”

*Read the Bay Nature article, understand it’s history, and see just how important this land is to countless species.

The icon of wildlife conservation, the Giant Panda, is feeling  the squeeze of habitat fragmentation.  As urbanization encroaches on wildlife corridors, the panda is left with an inability to traverse habitats and find suitable mates.  According to a recent news report citing the World Wildlife Foundation, the lack of available mates is increasing the chances of inbreeding, which may leave the panda population vulnerable to disease and decrease their capacity to reproduce. And that may mean extinction in 2-3 generations.

The case of the giant panda relates to the concept of constraint and tradeoff in evolution because specialization is a byproduct of adaptation.  Over time, natural selection has shaped the panda population to the chosen environment.  In order to capitalize on the available resources, the panda has traded genetic variation and has for all practical purposes permanently lost alleles for long-term success; a success that will continue as long as environmental conditions remain constant. Thus, herein lies the tradeoff and constraint of being specialized.

I most certainly believe evolutionary constraints have a hand in the endangered status of the giant panda.  Because the species is a specialized feeder and has a low fecundity, it limits ability to rapidly adapt to fluctuating environmental conditions.  If changes were to occur over a fairly long period of time, sure the panda MAY be able to adapt via the process of natural selection.  However, because alleles and genetic variation have been lost, the species is evolutionarily constrained and unable to adequately cope with the rapid decline in available habitat/resources.  I remember a phrase from some past conservation reading that sums the concept up rather nicely… “What a population was limits what it can be- at least in the short-term.”

And in the irony of expansion, many species with the ability to successfully integrate into urban landscapes  (i.e. coyotes) are deemed as unwanted invaders.   Thus, when fragmentation proliferates and open spaces are lost, it is not only the specialists that are under immediate threat, but even highly adaptable species.

During a recent drive down the urban drag I was tipped off to some new construction by the ‘subtle’ activities of an earthmover doing, well, moving earth around.  Apparently the city of Antioch, CA has broken ground on a Community Center adjacent to an approximately 5 year old water park, and a neighboring group of burrowing owls.

My initial thought was to chalk another point in the column of local urbanization and who could blame me as I have steadily watched cities continue the Manifest Destiny mantra and sideline open spaces and native wildlife with expansionism.  But, after a little investigation I was amazed to find the city was touting the establishment of a burrowing owl preserve and stated the following on their official website:

“As a part of our environmental impact mitigation for the new community center being built at Prewett park. We have developed 24 acres of preserved habitat for Burrowing Owls. This area will be preserved and maintained in perpetuity to protect these owls.”

Although urbanization is moving forward, perhaps I had jumped the gun in making wild accusations in my preliminary assessment?  Well, let’s not be too hasty.   Further reading of the project’s  Environmental Impact Statement (EIS) and the Burrowing Owl  Survey Protocol and Mitigation Guidelines yielded some interesting information. In 2005, biological surveys revealed at least 9 burrowing owls (including 2 pairs) were inhabiting the undeveloped ~70 acres of land in the park’s property.  The survey report continued by indicating that the “California Department of Fish and Game typically requires 6.5 acres of mitigation habitat for every pair of owls or unpaired individuals displaced by development.” Subsequent surveys over the next 3 years showed that of the 9 owls, 3 were actually residing in the 5.2 acre community center project zone and were subject to passive relocation…and hence the city’s establishment of the 24 acre preserve.

The reason for mitigation is that burrowing owls are a California species of special concern and a candidate species by the U.S. Fish and Wildlife Service.  As per the California Burrowing Owl Consortium, “…nearly 60% of the breeding groups of owls known to have existed during the 1980s had disappeared by the early 1990s.”

Now getting back to the story, a number of aerial maps in the EIS really caught my eye and provoked additional thought.  When the owls and occupied burrows are plotted, it becomes quite evident that the population is not clustered in a small region of the ~70 open acres of habitat, but are spread throughout.  Which makes sense as the owls need to ensure adequate food is available per individual or pair and thus sustainable. (Larger image click this link http://journowl.com/wp-content/uploads/2009/04/bo-population.jpg)

The second aerial map highlights the burrowing owl preserve and as you can see leaves a substantial portion of habitat unaccounted for.  So, an email to the city’s project manager revealed that after taking into consideration the current water park, the construction of the new community center (5.2 acres) and the establishment of the preserve (24.5 acres), approximately 40 plus acres remains undeveloped.  Yes, I thought it was a little suspicious as well, which is why I asked about other planned projects.  According to the city, future development plans include about 20 acres. (Larger image click this link http://journowl.com/wp-content/uploads/2009/04/bo_habitat.jpg

Giving the city the benefit of the doubt (I know it is quite a leap of faith) that the remaining 20 acres will be used to extend the burrowing owl habitat, the fact that the owl population’s Prewett Park range has been reduced by more than half is testament to the reason why over the last 15 years burrowing owls have disappeared from significant portions of their California range.

Additionally, what ramifications will the construction of the 2009 5.2 acre community center have on the resident population and more importantly construction of a further  20 acres in the future? What about a dramatic reduction in available habitat? From the trends that have already been observed, it was a 60% decline in breeding groups.  As I see it now, a nature stroll in the not so distant days will involve a concrete path in the shadow of a community center amongst non-native flora with a sign designating a once populated burrowing owl habitat.

This is one situation where I would love to be proved wrong…time will tell.

Well after a week of battling a hosting issue, I am finally back online and able to access my account.  However, I think the headache will be worth it as the updates made to JournOwl.com will increase site usability , especially enabling visitor comments that I hope will spur discussion and continue to link ecologically minded individuals.

Now getting back to the hybridization question I started a few weeks back, I wanted to explore the role it has as an evolutionary tool.  Interspecific hybridization has been described as a window into the evolutionary process because they [hybrids] are a culmination of genetic material from previously isolated gene pools. Publications routinely recognize the importance of hybridization and introgression in the plant community, but as it turns out the implications in animal species is less defined. 

With the reduction of natural barriers and wildlife population numbers, I wonder if we are on the verge of witnessing an increase in the interaction of species that at one time practiced genetic separation.  I’ve already mentioned some newsworthy specimens such as blue/fin whale and polar/grizzly bear hybrids in the previous post, and there are many more especially in fish of the U.S. Southwest, but where do these genetic middlemen fit in as far as diversification and evolution?

Typically speaking, hybrids  have a combination of genes that have not withstood the test of time and as such have not been evolutionarily fine-tuned.  Thus, hybrid individuals often display biological differences like faster or slower growth and reproductive inefficiencies, behavioral proclivities that make it difficult to find mates, and physiological traits that may increase predation.  Because of the repercussions, hybridization usually finds itself as a dead end, but not always.

There have definitely been successful species produced as a result of hybridization, and perhaps as habitats continue to undergo rapid changes and populations diminish sharply we will encounter more and more hybrids that have suddenly become ecologically efficient and filling new niches.  After all, species are not in a position to wait for gene combinations to be fined-tuned through evolution.  Maybe it is time to update the age old species adage “Adapt, Migrate, Die” and add Hybridize as a fourth option.

According to J. Mallet in 2005, “Phylogenetic hotspots, where approximately 25% of animal species hybridize, include British duck and game bird species, and American warblers and butterflies, but overall, 6–12% of bird, butterfly, and mammal species hybridize naturally.”

Not quite as exciting to the average person as hybrid mammals, a recent study has provided evidence that hybridization amongst corals has contributed to reef diversity and resilience, and has been “instrumental in their diversification on evolutionary timescales. Evidence that coral hybrids colonize marginal habitats distinct from those of parental species’ and that hybridization may be more frequent at peripheral boundaries of species’ ranges supports a role for hybridization in range expansion and adaptation to changing environments. We conclude that outcomes of hybridization are significant for the future resilience of reef corals and warrant inclusion in conservation strategies (Willis, BL. 2006. The role of hybridization in the evolution of reef corals. Annu. Rev. Ecol. Evol. Syst. 37:489–517).”

Picture: Mallard Hybrid, FWS (2006)

If you are a fan of National Geographic then I am sure you have witnessed their latest awe inspiring venture into the “Kingdom of the Blue Whale”, and if not, what are you waiting for!  I don’t want to get sucked into rehashing the program itself, but the point I was most interested in was the discussion of blue and fin whale hybrids.  An event that is very rare in terms of documentation, with observations topping out at a mere 11.  Ironically, the “Kingdom of the Blue Whale” was followed up by a documentary highlighting the 2006 discovery (killing) of a Polar bear/Grizzly hybrid.  Yes, perhaps old news now, but it was the perfect catalyst to jot down a few notes on hybridization and the potential problems, or maybe evolutionary strategies, it poses to biodiversity.

Extinction through hybridization generally manifests itself in three ways, but a fourth may be on the horizon:

1) Introduction of exotic and invasive species providing a means for gene pool mixing (introgression).  Examples include breeding between feral domesticated cats and wildcats, Felis silvestris, in Scotland as well as in African wildcats, Felis libyca.  More well known examples have popped up with reintroduction efforts of the red wolf, in which conservationists have uncovered gray wolf and coyote DNA in the genes of this endangered mammal.

2) Changes to habitat that bring once isolated species together.  Local and regional habitat modifications including clearcutting, agriculture and even reforestation have resulted in tree frog hybridizations and the interbreeding  between blue-winged warblers and golden-winged warblers.

3) Direct human interference.  Conservation efforts involving attempts to rescue dwindling populations by crossbreeding related species or subspecies, introduction of closely related species to enhance wild animal stocks (Florida panther, wood bison, wisent), or through wildlife farming (i.e. salmon) in which such individuals when released into the wild interact with natural populations. 

4) Indirect human interference.  Species with depleted numbers, which may actually be directly human-induced, are unable to find mates of their own species locally, and/or are forced to travel further and into new regions in search of food, mates, and suitable habitat.  By migrating out of traditional habitat or by simply a lack of numbers, animals come into contact with once isolated species, a process that perhaps created evolutionarily distinct species in the first place. As species co-mingle the chances of interbreeding increases as does introgression. 

In the case of blue/fin whales and polar/grizzly bears, all of these species are listed in the U.S. as threatened and endangered, which leads one to believe that there just might be something to indirect human induced hybridization.  Out of a shear will to survive, nature finds a way and with dwindling wildlife populations, shrinking habitats, climate change, clearcutting, urbanization, human population growth, noise pollution, and all the other usual suspects I believe we should not really be surprised by this response. 

Stay tuned next week for The Hybridization Evolution Strategy.

Five months before the passage of the Migratory Bird Treaty Act in 1918, an article was published in the NY Times proclaiming that our Nation’s gamebirds were under threat of extinction.  Interestingly enough the article contained a quote by Dr. E.W. Nelson, Chief of the U.S. Bureau of Biological Survey, that has transcended North American borders and become worldly relevant 90 years later.

“If you slaughter hundreds of thousands of these birds in Louisiana in winter for food, why wouldn’t it be just as fair for Canada to put hundreds of thousands of their eggs in cold storage for food in nesting time?  At that rate, how long would it be before every other state in the Union would be without these gamebirds?”

Times and the cause of migratory bird threats and declines may have changed, but the task of their preservation remains an international responsibility. Unlike the commercial trade in birds, feathers, and eggs in the early 1900’s that led to decimated bird populations, current declines are attributed to the increasing loss of habitats and environmental contaminants and pesticides. With Latin America boasting the highest rate of deforestation in the world, losing about 2 million acres of forest per year, and North America facing forests marred by fragmentation, development, clear cutting and roads, and wetlands drained for developers and farmland, it should not be a surprise that migratory birds are disappearing from our skies.  Because migratory birds require multiple areas for wintering, breeding, and stopover points, their decline is not the responsibility of one nation, but a global issue that needs to be addressed.

When it comes to current threats, we typically find the usual suspects, and for good reason, occupying the environmental headlines.  Loss of open spaces and habitat due to encroaching human population, growth and urbanization is principally responsible for bird declines.  An overabundance of pollution that includes more than 4 million tons of pesticides applied annually in the U.S. expose some 670 million birds to toxins, of which approximately 67 million birds are estimated to die right away. Oil and wastewater pits in the Western states kill up to 2 million birds each year according to the USFWS, and tens to hundreds of thousands of seabirds die as bycatch in U.S. fisheries each year.

But a lesser known pollution culprit is putting a spotlight on the plight of migratory birds too.  Those bright cityscapes might look great on a horizon, but are wreaking havoc on nighttime navigating birds. Sending birds off course or crashing into buildings is not something we intend, but is a consequence of an ever increasing amount of light pollution. In the January 2009 Frontiers in Ecology and the Environment, the publication Polarized light pollution: a new kind of ecological photopollution has linked smooth dark surfaces with highly polarized reflected lights, which are believed to be mistaken for bodies of water.  “The alteration of natural cycles of light and dark by artificial light sources has deleterious impacts on animals and ecosystems.”

With more than 900 million birds estimated to die as a result of collisions each year, maybe it is time to dim our lights (at least in part realistically) and leave lighting the night to celestial bodies.

Overfishing is rearing its ugly head once again and I am quite certain the repercussions of depleting our world’s fish stocks will continue to directly (and indirectly) strangle a multitude of species. Taking center stage are 7 tuxedo-clad species threatened by commercial fisheries, increased competition for prey, habitat loss and degradation, disease, predation, and climate change.

The technological boom over the last 60 years has catapulted the fishing industry into a commercial titan, enabling ships to continue fishing ocean waters for weeks before returning home with bursting hulls. Now fast forward to the 21st century and it should be no surprise that the annual global fish catch is in excess of 100 million tons (as of 2004) and at least 33% of the world’s fish stocks are overfished.

Apparently this means more than an empty slot in the seafood counter and mere inconveniences for shoppers as penguins and other wildlife do not have the luxury of skimming through grocery stores for their next meals.

The U.S. Fish & Wildlife Service has found the African penguin (Spheniscus demersus) is in danger of extinction due to a dramatic decline in numbers caused by oil pollution and overfishing. Besides the decrease in available prey, reduced fisheries are increasing the pressure on penguin predation as predators are expanding their diets and/or focusing efforts on species that are readily accessible.

This is a classic example of what is touted in environmental circles regarding interdependence amongst species and ecosystems, and thanks to the landmark “March of the Penguins”, listing some of the now famous emperor penguin’s brethren may be the spark required to initiate the cute factor and gain society’s attention to the plight of our dwindling fisheries.

Besides the African penguin’s proposal for an endangered listing, the FWS recommends 6 penguin species for threatened status:

• the yellow-eyed penguin (Megadyptes antipodes)
• the white-flippered penguin (Eudyptula minor albosignata)
• the Fiordland crested penguin (Eudyptes pachyrhynchus),
• the erect-crested penguin (Eudyptes sclateri)
• the Humboldt penguin (Spheniscus humboldti)
• the Southern Rockhopper penguin (Eudyptes chrysocome) in part of its homerange