Posts Tagged ‘Ocean’


Florida Red Tide Kills Hundreds of Manatees

Wednesday, April 10th, 2013

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Red Tide is the scourge of west coast Florida beaches. For the many years I lived there, this almost yearly algae bloom would kill thousands of fish which would then wash up on the Gulf Beaches and stink. This year the Red Tide has added a new victim, the slow moving, graceful and beloved manatees of the Florida West Coast.

Apparently, Red Tide algae can be toxic when consumed by manatees, as it causes them to become paralyzed. The paralyzed manatees eventually drown as they cannot return to the surface for air. According to the Tampa Tribune, authorities believe that approximately 200 Manatees were killed this year by Red Tide. Even though the bloom has dissipated, manatee deaths can continue for several months as the toxins settle onto the Sea Grass, the manatees major food source. manatees are on the Federal endangered Species List and have been protected by Florida Law since 1893. The deaths this year have reduced the manatee population by approximately 10%.

As any Floridian can tell you, manatees are wonderful mammals. They are gentle vegetarians that can reach up to 13 feet long and weigh up to two tons. They are distantly related to elephants and aardvarks. Manatees have also been known to body surf or barrel roll when playing. They have no major predators, but their biggest foe is us! According to Save the Manatee Club, “Florida’s West Indian manatees have no natural enemies, and it is believed they can live 60 years or more. As with all wild animal populations, a certain percentage of manatee mortality is attributed to natural causes of death such as cold stress, gastrointestinal disease, pneumonia, and other diseases. A high number of additional fatalities are from human-related causes. Most human-related manatee fatalities occur from collisions with watercraft. Other causes of human-related manatee mortality include being crushed and/or drowned in canal locks and flood control structures; ingestion of fish hooks, litter, and mono-filament line; and entanglement in crab trap lines. Ultimately, loss of habitat is the most serious threat facing manatees in the United States today. There is a minimum population count of 4,834 manatees, as of January 2011.”

Tampa’s Lowry Park Zoo has managed to rescue about 10 of the Manatees affected by Red Tide toxins. All have survived and 4 were recently released into a sanctuary away from the Red Tide and speeding boat propellers.

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Beach Erosion – When It’s Man vs. Nature – Nature Naturally Wins!

Tuesday, January 15th, 2013

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I just spent another week in one of our favorite places, Sarasota, Florida. The weather was great and everyone had a wonderful time. My wife Gail and I lived there from 1978 until 1983, and have been visiting there every year since then. There have been many changes, new developments, buildings, hotels, shopping centers, etc. We have lost many of the old family stores and restaurants to have them replaced by newer fancier ones.

However, by far the greatest change that I see from year to year are the beaches themselves. This year it was even more pronounced due to the effects of Tropical Storm Debbie that swept through the area June 26, 2012. Ten to 30 feet of sand were eroded from beaches in Sarasota County.

Erosion of beaches is nothing new. There has been several attempts to replenish the beach and there is an official presentation on the City of Sarasota’s website about the Lido Beach Restoration.

As much as I love the beach, the fallacy behind any beach restoration or replenishment is that we can “fix” a naturally occurring process, the ever changing relationship between water, wind and sand. According to the Center for Ocean Solutions, coastal erosion is a natural process along the world’s coastlines that occurs through the actions of currents and waves and results in the loss of sediment in some places and accretion in others. Erosion is considered to to be sporadic and episodic. There can be large scale erosion in only a few hours with a severe storm (episodic) and different areas can erode at different rates even during the same event (sporadic).

Here are examples of erosion in the Florida Panhandle at Navarre Beach due to two hurricanes. The upper photo was taken on July 17, 2001, the middle photo was taken on September 17, 2004, one day after the landfall of Hurricane Ivan, and the lower photo was taken on July 12, 2005, two days after the landfall of Hurricane Dennis. This is a clear example of the episodic nature of beach erosion. (Click image to enlarge)

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Scientific American stated in its EarthTalk column that coastal erosion in any form is usually a one-way trip. Man-made techniques such as beach nourishment—whereby sand is dredged from off-shore sources and deposited along otherwise vanishing beaches—may slow the process, but nothing short of global cooling or some other major geomorphic change will stop it altogether. U.S. Environmental Protection Agency estimates that between 80 and 90 percent of the sandy beaches along America’s coastlines have been eroding for decades. In many of these cases, individual beaches may be losing only a few inches per year, but in some cases the problem is much worse.

According to Stephen Leatherman (“Dr. Beach”) of the National Healthy Beaches Campaign, building a bulkhead or seawall along one or a few coastal properties may protect homes from damaging storm waves for a few years, but could end up doing more harm than good. “Bulkheads and seawalls may accelerate beach erosion by reflecting wave energy off the facing wall, impacting adjacent property owners as well,” writes Leatherman, adding that such structures along retreating shorelines eventually cause diminished beach width and even loss.

Other larger scale techniques like beach nourishment may have better track records, at least in terms of slowing or delaying beach erosion, but are expensive enough as to warrant massive taxpayer expenditures. Beach nourishment is the process of adding new sand to the beach profile in order to restore it to some former width. This is usually accomplished by dredge and fill operations with sand pumped onto the beach from an offshore source, such as sand bars or shoals. Beach nourishment is only feasible at the community level as large sectors (e.g., miles of the shore) must be nourished to be economical viable. In the early 1980s, Miami Beach was restored at the cost of $65 million along this 10-mile strand of shore.

There have been over 8 beach nourishment projects on Lido Beach at a cost of over $12 Million Dollars. However, the beach continues to erode. Here are pictures I took last week showing significant recent erosion on Lido Beach.

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With the expected rise in sea levels and the increase in both the frequency and severity of storms being attributed to global climate change, one can expect that coastal erosion will continue to increase. The U.S. government’s Environmental Protection Agency states that if sea levels increase by one foot, would erode most of Florida Beaches 100 to 200 feet. They also believe that sea levels could rise as much as 3 feet over the next 100 years. The cost to replenish the lost sand would be $8 Billion.

While it is understandable that areas with expensive homes and condominium projects and whose economic base is dependent on tourism will continue to spend large sums on beach replenishment projects. While this may be futile in the long run, short term it still allows for a wonderful beach experience as these photos from last week will show.

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Also, if you didn’t click the “sand” link earlier in the article, take a second to check out this cool slideshow. It gets up close with what our beaches are made out of, Sand of course!
Click here to view the slideshow.