Indian River Lagoon

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Indian River Lagoon
IndianRiverLagoon.jpg
Aerial view of Indian River Lagoon
Indianriverlagoon.GIF
Map of lagoon and surrounding area
Location Florida, United States
Length 251 km (156 mi)
Source elevation 0
Basin area 2,187.5 sq mi (5,666 km2)

The Indian River Lagoon is a grouping of three lagoons: Mosquito Lagoon, Banana River, and the Indian River, on the Atlantic Coast of Florida. It was originally named Rio de Ais after the Ais Indian tribe, who lived along the east coast of Florida.

History[edit]

From 1913 to 2013, activity by humans has increased the watershed for the lagoon from 572,000 acres (231,000 ha) to 1,400,000 acres (570,000 ha) increasing runoff of freshwater and nutrients from farms. Both have been detrimental to lagoon health.[1]

The wetlands are needed to cleanse the lagoon. About 40,000 acres (16,000 ha) of land were lost to mosquito control. These have been restored, but by 2013, recovery was incomplete.[1]

From 1989 to 2013, the population increase along the lagoon has risen 50% to 1.6 million people.[1]

Seagrass is the greatest measure of lagoon health. By 1990, it had surpassed levels reached in 1943. In 1990, the Florida Legislature passed the Indian River Lagoon Act, requiring most sewer plants to stop discharging into the lagoon by 1996. Some sports fish rebounded in population in the 1990s when gill nets were banned and pollution in the lagoon was reduced. But 2013 algae blooms and loss of sea grass destroyed those gains.[1]

In 2007, concerns were raised about the future of the lagoon system, especially in the southern half where frequent freshwater discharges seriously threaten water quality (decreasing the salinity needed by many fish species) and contribute to large algae blooms (water heavily saturated with plant fertilizers promote the algae blooms). The lagoon has also been the subject of research on light penetration for photosynthesis in submerged aquatic vegetation.[2] The seagrass covers over 100,000 acres (40,000 ha) and is a critical component to the overall health of the lagoon.[2][3]

In 2010 3,300,000 pounds (1,500,000 kg) of nitrogen and 475,000 pounds (215,000 kg) of phosphorus entered the lagoon.[4]

In 2011, a superbloom of phytoplankton resulted in the loss of 32,000 acres (13,000 ha) of lagoon seagrass. In 2012, a brown tide bloom fouled the northern lagoon. The county has approval for funds to investigate these unusual blooms to see if they can be prevented.[5]

Catches of blue crabs have dropped unevenly from 4,265,063 pounds (1,934,600 kg) in 1987 to 389,795 pounds (176,808 kg) in 2012, but with high catches in 1998, 1991, alternating with low catch years. These crabs require 2% salt content in the water to survive. A drought increases the salt content; heavy rainfall decreases it. Both of these conditions have recurred over the past decades and are believed to have had an adverse affect on the crab population.[6]

In 2013, there were four major problems with water quality in the lagoon. 1) Excess nitrogen and phosphorus from runoff from the application of fertilizer; 2) an estimated 8 to 11% septic tank failure. There are tens of thousands of septic tanks in the county. 3) Muck from construction, farming, erosion and dead plants, all find their way to the bottom of the lagoon, preventing growth and consuming vital oxygen essential to marine flora and fauna; 4) Invasive species, including the Asian green mussel, South American charru mussel, and the Australian spotted jellyfish, all eat clams and fish larvae.[7]

Mangroves are important to marine life. Between the 1940s and 2013, 85% of them had been removed for housing development.[1]

Course[edit]

Its full length is 156 miles (251 km), extending from Ponce de León Inlet in Volusia County, Florida, to Jupiter Inlet in Palm Beach County, Florida,[8][9] and includes Cape Canaveral. Lake Okeechobee is connected to the lagoon by the Okeechobee Waterway and the St. Lucie River meeting in Sewall's Point.

Portions of the Lagoon, from north to south:

Natural history[edit]

The Indian River Lagoon is North America’s most diverse estuary with more than 4,300 species of plants (2,100) and animals (2,200), including 35 that are listed as threatened or endangered — more than any other estuary in North America.[10][11] The lagoon has about 2,500 types of animals in it.[clarification needed] The Lagoon varies in width from .5 to 5 miles (0.80 to 8.05 km) and averages 4 feet (1.2 m) in depth.[10] It serves as a spawning and nursery ground for many different species of oceanic and lagoon fish and shellfish. The lagoon also has one of the most diverse bird populations anywhere in America. Nearly 1/3 of the nation’s manatee population lives here or migrates through the Lagoon seasonally. In addition, its ocean beaches provide one of the densest sea turtle nesting areas found in the Western Hemisphere.

Red Drum, Spotted seatrout, Common snook, and the Tarpon are the main gamefish sought by anglers in the Titusville area of the lagoon system.[12]

Dolphins[edit]

Between 200 and 800 Bottlenose dolphins (Tursiops truncatus) normally live in the Indian River Lagoon. The dolphins resident in the lagoon system may belong to three or more different communities. There is little exchange of individuals between the lagoon and coastal populations. However, individuals from coastal populations are occasionally seen in the lagoon. One individual from the lagoon communities, Dolphin 56, was tagged in the lagoon in 1979 and was sighted in the lagoon more than 40 times through 1996. In 1997 Dolphin 56 left the Indian River Lagoon and was spotted many times along the east coast of the United States from Florida to New York into 2011.[13][14]

Female Bottlenose dolphins in the Indian River Lagoon tend to live longer than males. The maximum age attained by both sexes is one to almost two decades less than that reached by dolphins resident in Sarasota Bay, the most thoroughly studied wild population of Bottlenose dolphins.[15]

Economy[edit]

The diversity of the lagoon draws millions of boaters and fishermen annually, which brings tens of millions of dollars to Florida. In 2007, visitors spent an estimated 3.2 million person-days in recreation on the lagoon.[16]

In 2008, Hazen and Sawyer,P.C. submitted a report titled “Indian River Lagoon Economic Assessment and Analysis Update” to Troy Rice, Director of the Indian River Lagoon National Estuary Program, St. Johns River Water Management District. The report described the estimated 2007 recreational uses and economic value of the Indian River Lagoon to residents and visitors of the five counties that comprise the Lagoon system. The sum of recreational expenditures and recreational use value was $2.1 billion (See Section 7).[17]

See also[edit]

Citations[edit]

  1. ^ a b c d e Waymer, Jim (October 13, 2013). "Talking solutions". Florida Today (Melbourne, Florida). pp. 6A. Retrieved October 19, 2013. 
  2. ^ a b Hanisak, M. Dennis (1997). "Continuous Monitoring of Underwater Light in Indian River Lagoon: Comparison of Cosine and Spherical Sensors.". In: EJ Maney, Jr and CH Ellis, Jr (Eds.) The Diving for Science…1997, Proceedings of the American Academy of Underwater Sciences, Seventeenth annual Scientific Diving Symposium. Retrieved 2009-04-02. 
  3. ^ Dawes, Clinton J.; M. Dennis Hanisak, and Judson W. Kenworthy (1995). "Seagrass biodiversity in the Indian River Lagoon". Bulletin of Marine Science 57 (1): 59–66. Retrieved 2009-04-02. 
  4. ^ "Editorial:Dying dolphins". Melbourne, Florida: Florida Today. 22 May 2010. pp. 13A. 
  5. ^ Waymer, Jim (April 25, 2013). "Panel approves $1.2 million in lagoon projects". Florida Today (Melbourne, Florida). pp. 2B. 
  6. ^ Waymer, Jim (September 8, 2013). "Lagoon crab catches dwindle". Florida Today (Melbourne, Florida). pp. 1A,3A. Retrieved September 13, 2013. 
  7. ^ Waymer, Jim (September 29, 2013). "Do something!". Florida Today (Melbourne, Florida). pp. 4A. 
  8. ^ Indian River Lagoon Comprehensive Conservation Management Plan
  9. ^ Indian River Lagoon.com Indian River Lagoon
  10. ^ a b http://www.sjrwmd.com/itsyourlagoon/pdfs/IRL_Natural_Treasure_book.pdf
  11. ^ http://www.sjrwmd.com/irlinsert/
  12. ^ http://www.abouttitusville.com/outdoors/fishing/IRL1.html
  13. ^ *BOTTLENOSE DOLPHIN (Tursiops truncatus) Indian River Lagoon Estuarine System Stock
    Smithsonian Marine Station at Fort Pierce - Tursiops truncatus - Habitat and Distribution
    Field Study - Indian River Lagoon Dolphins - Dolphin 56 Sighting Ssummary
  14. ^ Soper, Shawn J. (May 6, 2011). "Dolphin 56 Back Dazzling Boaters In Ocean City". The Dispatch (Ocean City, Maryland). Retrieved 6 June 2012. 
  15. ^ Stolen and Barlow:645
    Mote Marine Laboratory - Dolphin Research Program
  16. ^ "Visitors spend big on the lagoon". Indian River Lagoon Update XVI (3): 1. Summer 2008. 
  17. ^ http://www.sjrwmd.com/itsyourlagoon/pdfs/IRL_Economic_Assessment_2007.pdf

References[edit]

  • Stolen, Megan K. and Jay Barlow. (October 2003) "A Model Life Table for Bottlenose Dolphins (Tursiops truncatus) from the Indian River Lagoon System, Florida, U.S.A." Marine Mammal Science.19(4)630-649. Found at [1]

External references[edit]

Coordinates: 28°03′19″N 80°34′34″W / 28.05528°N 80.57611°W / 28.05528; -80.57611