FISHES, MACROINVERTEBRATES, AND HYDROLOGICAL CONDITIONS 

 OF UPLAND CANALS IN TAMPA BAY, FLORIDA' 



William N. Lindall, Jr., John R. Hall, and Carl H. Saloman^ 



ABSTRACT 



Faced with statutory restraints that prohibit dredging and filling of estuarine bottoms, 

 coastal developers have turned to alternate methods of providing water front property 

 for homesites. One method, recently used in Tampa Bay, Fla., is the construction of 

 access canals that lead from open water to upland acreage. 



This paper presents biological and hydrological data from new upland canals together 

 with some comparative data from older upland canals and bayfill canals. In all types of 

 canals, as presently engineered, stratified, stagnant water causes low levels of dissolved 

 oxygen in summer months, resulting in mortality or emigration among resident organisms. 

 Means of alleviating the problems are discussed. 



Among Florida's 322,000 ha of estuarine habitat 

 less than 2 m deep, about 24,000 ha have been 

 filled by coastal developers (Marshall, 1968). 

 Public indignation over indiscriminant and un- 

 regulated exploitation of these areas has stimu- 

 lated legislative action designed to conserve and 

 protect natural resources in estuarine areas that 

 remain (Linton and Cooper, 1971). Faced with 

 statutory restraints, coastal developers have, in 

 some instances, abandoned plans for further bay 

 filling and now seek alternate ways to create pre- 

 mium homesites that will satisfy ever-increasing 

 public demand for waterfront property. One 

 way is the construction of access canals that lead 

 from open water to upland acreage (Barada and 

 Partington, 1972). This method was recently 

 used in Tampa Bay in northeast St. Petersburg, 

 Fla., to connect a housing development with the 

 estuary. 



Shortly after draglines removed earth plugs 

 between the excavated canal system and the bay, 

 property owners gave this Laboratory permis- 

 sion to monitor the canals so that ecological con- 



ditions in the manmade waterways could be doc- 

 umented. This report contains ecological data 

 recorded at canal and control stations during the 

 first 13 months after the waterway system was 

 completed. Conditions within the upland canal 

 are compared with those recorded in bayfill ca- 

 nals of Boca Ciega Bay, Fla., and older upland 

 canals. 



DESCRIPTION OF AREA 



The study area, known as Tanglewood Estates, 

 is located at the southern end of Old Tampa Bay 

 on a tract of land that was originally drained 

 by a small tidal inlet of approximately 0.5 ha 

 (Figures 1 and 2) . During development, the in- 

 let was dammed and pumped dry. Canals were 

 dug to a depth of approximately 4 m below mean 

 low water and stabilized by concrete seawalls 

 (Figure 3). Bay water was introduced into the 

 ditches in June 1970 creating a canal system of 

 approximately 1.6 ha. Average tidal range in 

 the canal svstem is about 1 m. 



' Contribution No. 78, Gulf Coastal Fisheries Center, 

 St. Petersburg Beach Laboratory, National Marine Fish- 

 eries Service. 



^ Gulf Coastal Fisheries Center, National Marine Fish- 

 eries Service. NOAA, 75 33d Avenue, St. Petersburg 

 Beach, FL 33706. 



Manuscript accepted July 1972. 



FISHERY BULLETIN: VOL. 71. NO. 1, 1971. 



PROCEDURES 



Hydrological (five stations) and biological 

 (four stations) samples were collected monthly 



155 



