China's Yangtze River has been described as the "Asian Amazon" and, as seems to befall many large rivers in growing nations, it has seen its share of perils from urban development, commercial use, and industrial pollution. Unfortunately, many of the river's inhabitants pay the price - including the river's dwindling population of freshwater cetaceans.
The Baiji - a freshwater river dolphin with an unusual, elongated jaw/beak that roamed the Yangtze for tens of thousands of years - was declared extinct in 2007, eliminated from the planet in a matter of a few decades.
And now another rare dolphin species is facing a similar fate. As reported in the BBC Earth News, a new study published in the Marine Biology journal, says that the river's remaining population of finless porpoises are headed for extinction. The finless porpoise (so named because it lacks a dorsal fin) lives in the Yangtze, Yellow Sea, and South China Sea; and according to the study, there are genetic differences between the various populations. This would indicate that there is no co-mingling between the groups and this can add to their inability to withstand adverse changes to one group's environment.
This type of isolation and loss of mixing of the DNA gene pool is also what threatens land animal populations, like some of the wolf packs in the north central United States.
With everything from human waste and industrial chemical pollution, boat traffic, and commercial fishing taking place in the Yangtze River, the rapidly declining freshwater population of the finless porpoise - numbering less than 1,000 when last estimated in 2006 - will not survive without strong action on the part of the Chinese government.
The only hope is for a fundamental change in attitude in China regarding its aquatic natural resources. And there is some evidence of that which could produce results, hopefully before it is all too late.
While a major producer of CO2 emissions and the greatest exporter of seafood of any country, China is also realizing the environmental impact its economic growth is having on itself. The country is making sizable investments in alternative energy and, according to the Seafood Choices operational arm of SeaWeb, China's seafood distributors are beginning to show some interest in sustainability. Seafood Choices is holding seminars with seafood exporters in advance of a Sustainable Seafood Forum to be held in China this November.
Whether all of this will produce changes that will come in time to save the finless porpoise remains questionable at best. It is unfortunate that humans seem to be a reactionary species, responding to a tragedy that might spell a better future for some but leaving victims - like the Biaji and the finless porpoise - as reminders of what we could have done if only for a little foresight.
Read about the finless porpoise in BBC Earth News.
Read about SeaWeb/Seafood Choices progress in China.
There's one marine animal that, frankly, I don't pay much attention to in this blog and that is sea birds. Except for concern over their uncanny ability to bomb our cars, hats, and docks with globs of white, many people don't give them much thought - maybe the occasional shot of an oil-soaked sea gull catches our eye, but beyond that . . .
But these animals are at the mercy of environmental change like pollutants or global warming, just like any other species. And their loss would be ours too, as they play a role in maintaining a balanced ecosystem.
I was reviewing summaries of several scientific papers and found some interesting issues confronting several species:
One study looked at red knots that frequent the U.S. east coast. This time of year, red knots congregate in the Delaware Bay to feed on horseshoe crab eggs before they continue their northward Arctic migration to breed. The demand for horseshoe crabs as bait has dramatically increased over the past two decades, thereby greatly reducing the supply of eggs for the red knots. This has impacted the survivability rate of the red knot and returning populations in the Delaware Bay have dropped as much as 75 %. Of concern is that while efforts have been made to increase the horseshoe crab population, the number of red knots has not increased in kind.
Another study showed that Cassin's auklet, a cold-water sea bird, could face serious population declines due to climate change because, as a zooplankton feeder, it depends on prey like the copepod N. cristatus whose population drops when warmer waters are prevalent. The study showed that in past years, the population of the auklet fluctuated in direct correlation with copepod numbers that were impacted by warmer water temperatures. As temperatures consistently warm up, the auklet is at risk.
Not all is necessarily bad news. While some animals suffer from climate change because of an inability to adapt, the razorbill seems to be adjusting as it's dispersal and range has reported to have increased northward into the Canadian Arctic due to the northward movement of its fish prey, like capelin. As temperatures increase and a variety of flora and fauna expand their range, some animals are able to adjust, while others perish due to loss or reduction of prey or food.
If you adhere to the evolutionary concept of birds being ancestors of ancient dinosaurs, then it can truly be said that they are highly adaptive creatures. But with their long range migrations and breeding habits based on certain environmental conditions, there is a question as to their future in the face of what is happening today. Research is ongoing to determine the long-term effects of pollution and climate change on our feathered friends.
I'm sure you have heard about the challenges faced by our coral reefs. Researchers are saying that from 25% to 50% and more of our corals reefs are showing definite decline due to pollution, changes in water temperature, and other effects that can be attributed to man-made activities.
Because of the low level of nutrients in tropical waters, coral reefs have often been described as oases in the desert. And we are still learning just how they are able to survive in such a beautiful but harsh environment.
A recent report explores one component that contributes to the delicate web of a healthy reef: cave sponges. Marine biologist Jasper de Goeij has been studying the role that these basic multi-celled animals play in maintaining the nutritional cycle of the coral reef. His studies show that corals and algae dispense organic compounds that few creatures can use as food. The sponges, however, filter this particulate matter as part of its normal process in filtering vast amounts of water to extract what little nutrients are available.
To protect and sustain itself against this intake of organic material (that can include viruses, bacteria, and other poisons) the sponge is continually rejuvenating cells and the dead cells it sheds form an organic material that can be utilized by many organisms on the reef. In this way, a cycle of mutual dependence is formed.
While our attention is often focused on the most colorful of the basic reef builders, the coral, we must always remember that a coral reef is a complex system with many organisms, plant and animal, playing important roles - sometimes behind the scenes and out of view - in maintaining a healthy tropical ecosystem.
Read article from Insciences Organisation.
The week-long International Coral Reef Symposium, being held in Fort Lauderdale, FL, wraps up today having brought together nearly 3,000 scientists to discuss issues and possible solutions to address the ongoing degradation of our coral reef ecosystems. Many of the results and discussions are making their way into scientific journals and newspapers worldwide.
You have all probably heard about how corals reefs have been negatively impacted by pollution, climate change, and the souvenir trade from the Caribbean to the South Pacific. The latest worldwide assessment of over 700 species shows 32.8% threatened with extinction, with a capital E. With the loss of these reefs, the inevitable domino effect follows with the loss of fish and other animal life - which carries an economic impact on tourism and subsistence fisherman in many of these tropical locales.
When I do underwater presentations as a volunteer diver at the Aquarium of the Pacific back home in Southern California, I try to impress upon the audience the importance of these marine ecosystems even though they may be thousands of miles away - they can never be "out of sight, out of mind."
- Non-biodegradable trash (plastic bags, styrofoam, etc.) and chemicals (oil, fertilizers) originating from the California coast, can travel thousands of miles to tropical locales.
- Carbon emissions and its subsequent effect on temperatures impact the coral in a variety of ways, from disrupting the symbiotic relationship of internally-stored zooxanthellae (single-celled algae) to an increase in external algae and bacteria that crowds out or kills coral species.
- Conversely, the loss of faraway coral reefs effects the chemical balance of the seas and the exchange of chemicals between sea and air, which in turn can affect temperature gradients, currents, and winds - all of which can impact us worldwide.
Just another example of all we're all connected - land, sea and air - from coral to humans, we're all part of Nature. Here's some links to learn more about what you can do: NOAA, Nature.org.
China's Yangtze River has been described as the "Asian Amazon" and, as seems to befall many large rivers in growing nations, it has seen its share of perils from urban development, commercial use, and industrial pollution. Unfortunately, many of the river's inhabitants pay the price - including the river's dwindling population of freshwater cetaceans.
The Baiji - a freshwater river dolphin with an unusual, elongated jaw/beak that roamed the Yangtze for tens of thousands of years - was declared extinct in 2007, eliminated from the planet in a matter of a few decades.
With everything from human waste and industrial chemical pollution, boat traffic, and commercial fishing taking place in the Yangtze River, the rapidly declining freshwater population of the finless porpoise - numbering less than 1,000 when last estimated in 2006 - will not survive without strong action on the part of the Chinese government.
