Title: Clams and Oysters in Charlotte County and Vicinity
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 Material Information
Title: Clams and Oysters in Charlotte County and Vicinity
Physical Description: Archival
Language: English
Creator: Woodburn, Kenneth D.
Publisher: Florida Board of Conservation Division of Salt Water Fisheries
Place of Publication: St. Petersburg, FL
Publication Date: March 1965
Copyright Date: 1965
 Record Information
Bibliographic ID: UF00089232
Volume ID: VID00001
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved by the source institution and holding location.

Full Text











Florida Board of Conservation
Division of Salt Water Fisheries









CLAMS AND OYSTERS IN CHARLOTTE COUNTY AND VICINITY



by



Kenneth D. Woodburn


Florida Board of Conservation Marine Laboratory
Maritime Base, St. Petersburg, Florida






Originally Mimeographed 1 August 1962
REISSUED March 1965





FSBCML NO.: 62-12


CS NO.: 62-1











FOREWORD


Fishing is Florida's oldest industry, Florida saltwaters produce

a greater variety of marine products, including game and food fishes,

than any other State. The combined value of the commercial and sports

fisheries, established by state-wide professional surveys, is at least

$300,000,000 yearly. The whole State, and all 35 coastal counties in

particular, share in this wealth a gift of Nature so long as they

judiciously exploit their shorelines, saltwaters and submerged bottoms*

The State Board of Conservation has a vested interest in seeing that

this is done. It is charged with the supervision, conservation and

development of the different fisheries through scientific management,

control and aquaculture based on research. The job is difficult.

Problems are acute because rapid urbanization has accelerated lucrative

waterfront development and unfavorable changes in marine environments.

Damage to our multi-million dollar fisheries is not inherent in

urbanization unless planning is poor and short-sighted and destructive

dredging, filling and pollution are condoned because of apathy, ignorance

or greed.

Coastal, estuarine and island development can be planned to best

serve conservation. The State Board of Conservation stands ready to

aid and advise counties, other governmental units and private interests

in the best known ways to sustain and further marine productivity.










CLAMS AND OYSTERS IN CHARLOTTE COUNTY AND VICINITY


Introduction

Charlotte is a county of change. Its population has tripled in

the last decade. Most of the new population is concentrated in water-

front communities whose homesites have been created by digging canals

to drain raw upland and provide navigable waterways. This surge of

people makes it imperative that affected shorelines, saltwaters and

submerged bottoms be judiciously exploited. Fortunately, hydraulic

dredging and filling of submerged land to make residential finger fills

has not been widely practiced in Charlotte as in Pinellas, Dade and

Palm Beach Counties where productive bay bottoms have been extensively

destroyed.

As pollution, pests and diseases, and declining yield continue to

plague northern shellfish areas, interest and enthusiasm in Florida as

a commercial shellfish producer grows* In our warm waters, clams and

oysters reach marketable sizes in about one-half the time they do in

New England and the Middle Atlantic States. Charlotte and Okaloosa

Counties have experienced the greatest increase in commercial shell-

fishing activity and interest in Florida. This study has been made in

recognition of the important role Charlotte County is playing in the

Florida seafood industry.

If the present boom in shellfish harvesting and culture is to

continue and succeed, bulkhead lines will have to be set at or near

mangrove shorelines and dredging as well as filling limited by the

bulkhead lines. The most realistic method to assure marine productivity

is to allow those low shorelands lying in the path of urbanization to be

raised to levels suitable for human habitation with fill material ob-

tained from draglining canals inside bulkhead lines.
-4-







Scale: 1" = 250,000"


/~


N
4/


(freshwater line)


Alligator Bay


Harbor


iglewood


Beach


Stump Pa8s

The Narrows.


Little


Pass


t


Hole


ill Bay


Bay


Map 1
Reference points and bodies of water in
County and gricinity


)P
0
r /



Charlotte

FSBCML NO.: 62-12
CS No.: 62-1


-5-


Cr.







Field investigations for this report were made intermittently from

June 5 through June 21, 1962 with the assistance of Officers William

King and Luke Wolcott of the Florida Conservation Patrol* Map 1 has

been prepared to orient the reader to reference points and bodies of

water. Water salinities and temperatures, tides, bottom types, abun-

dance and quality of clams &nd oysters, and shellfish predators were

noted.

Three species of bivalve mollusks have commercial significance in

Charlotte County and vicinity.

The Southern Quahog or hardshell clam, Mercenaria campechiensis, is

being harvested extensively from productive natural beds along the

inside of Gulf barrier islands.

The eastern oyster, Crassostrea virginica, is the basis for exten-

sive leasing of submerged bottoms especially in Turtle and Bull Bays.

Oyster harvesting has been mostly from natural bars also. These public

bars are closed to oystering from May 1st to September 1st each year so

that now oyster activity is limited mainly to seeding of leases, Coon

oysters refer to oysters that are stunted, poor quality and usually

overcrowded. AS spat or baby oysters, they settle in unfavorable

locations. If culled and moved to favorable environment, they can reach

marketable size and quality.

Large beds of the Rangia marsh clam, Rangia cuneata,in the brackish-

freshwater zones of the Myakka and Peace Rivers have commercial.concentra-

tions if processing proves economically feasible, marketing outlets

materialize and river water is certified for shellfish harvesting,

Recorded hardshell clam production began in Florida in 1880, in-

creased significantly in 1908 with exploitation of large clam beds in

Collier and Monroe Counties near the Ten Thousand Islands, grew steadily

until the peak year of 1932, remained at a high level through most of

World War II and plummeted to a beginning low by 1950, From 1950
-6-






production increased modestly, as shown on Table 1, until February 1962

when intensive harvesting of natural clam beds in Charlotte County and

vicinity began. Table 2 showi the dramatic jump in Charlotte County hard-

shell clam production preceded two months earlier by a sharp rise in

oyster production, Development of marketing outlets in Middle Atlantic

States caused the increase in hardshell clam harvesting.

Most shellfish leases have been for oysters, One oyster-shucking

plant operated in Placid this past season. Another is being constructed

nearby. It is very doubtful that production from natural bars in the

area could ever support two oyster houses. Leases will have to be

brought into production where mechanical harvesting is allowed. Oyster

shell planting for cultch was observed in Turtle Bay during field work

for this report. Oyster seed was being collected from coon oyster bars

in Gasparilla Sound.

Florida oysters and hardshell clams follow different paths to the

consumer. The oyster season coincides chiefly with the winter tourist

season. Most local oysters are consumed raw on-the-half-shell. Besides

shucking, and packing and chilling, processing of Florida oysters is

limited. Summer condition is poor because of spawning. The hardshell

clam is usually processed into chowder or a canned minced product. A

spawning condition is not so marked and there is no closed season de-

noting a period of poor quality.

Mechanical harvesting of clams and oysters lying in the path of

the West Coast Intracoastal Waterway is planned after contracts are let

for waterway dredging in Charlotte Harbor, Gasparilla Sound, Placida

Harbor and Lemon Bay. The waterway route generally follows deeper water

where harvesting of clams or oysters by hand or hand implements is

difficult or impossible especially for clams. Mechanical harvesting is

not allowed on public shellfish beds but in this case it would be

permitted because of the
-7-








TABLE I


Clam Production in Florida

(Pounds)*


YEAR EAST COAST WEST COAST TOTAL

18W0 5,000 -..-- 5,000

1903 57,000 182,000 239,000

1923 5,000 602,000 607,000

1930 49,840 661,736 711,576

1932 12,000 1,108,812 1,120,812

1940 6,700 701,100 707,800

1945 3,000 687,700 690,700

1950 900 4,400 5,300

1955 6,300 15,700 22,000

1960 2,134 23,893 26,027


* 5-,0 pounds

8.00 pounds


of meat per U. S. Standard Bushel (Florida East Coast)

of meat per U. S. Standard Bushel (Florida West Coast)


-8-









TABLE 2


Commercial hardshell clam and oyster production in Charlotte County
since increased exploitation of natural beds*


DATE HARDSHELL CLAMS OYSTERS

(pounds of meat)

May 1961 ------ Closed

June 1961 ..... season

July 1961 --...- for

August 1961 ..---- Oysters

September 1961 ------ .--

October 1961 ------ 192

November 1961 -..-- 2,204

December 1961 88 24,035

January 1962 ------ ----

February 1962 74,130 15,512

March 1962 22,330 8,524

April 1962 36,960 10,592



*Taken from Florida Landings- compiled by U. S. Fish and Wildlife
Service in cooperation with Florida State Board of Conservation
and the University of Miami Marine Laboratory.


-9-







probable destruction of shellfish by dredging, spoiling or siltation.

Special attention was given to waterway considerations during field

studies* The inherent difficulties in mechanical harvesting of shell-

fish before the waterway route is marked for dredging are obvious.

"Discovery" of the large beds of Rangia clams this year has roused

considerable interest in molluscan circles. Dr. Joseph P. Morrison,

Acting Curator, Division of Mollusks, U. S. National Museum, stated in

a letter to Dr. Robert F. Hutton:

"The bivalves you sent for identification, collected north of
Punta Gorda in the Peace River estuary, are readily identifiable
as Rangia cuneata (Gray).
The U. S, National Museum has eastern Florida records of this
species only from the St. Johns River (South of Jacksonville), and
from Lake Worth at Boynton. I have seen specimens from near Stuart,
Florida, in the Museum of Comparative Zoology collection at Cambridge.
On the west coast we have it from the Caloosahatchie River near Fort
Myers; from the East and Wakulla Rivers in the St. Marks region; from
Apalachicola; and from Pensacola.
Your specimens from the Peace River extuary help to fill in the
zoogeographic story of this brackish water species. It should also
be abundant in the lower Myakka River. You may recall that this is
one species that I am still searching for in the Tampa Bay area, to
parallel its fossil occurrence there. Does it live in the Manatee
River?
Rangia cuneata is an edible clam, belonging to the family
Mactridae. It is a close relative of the Hen or Surf Clam, Spisula
solidissima, one of the important clams commercially fished off the
Middle Atlantic States, and canned at Cape May, New Jersey, by the
Snow and other companies. J. A. Singley in 1893 reported that
Rangia cuneata (from the Galveston:region) had been canned and sold
commercially by the Givens Oyster Company under the name of "Little
Neck Clams". This report is in Singley's "Texas Mollusca", a part
of the 4th. Annual Report (1892) of the Geological Survey of Texas.
Rangia cuneata (presumably from Vera Cruz coastal lagoons) is
also served in restaurants in Mexico as far inland as Pachuca,
Hidalgo, in a clams and rice dish called "Paella a Valenciana".

Hydrographic studies (see Map 2 and Table 3):

Water salinity is to the shellfish farmer what soil pH is to the

general farmer, Hardshell clams, oysters and Rangia clams have different

optimal ranges of salinity just as wheat, corn and rye do:for pH. Lime

and fertilizer can alter soil conditions for the land farmer but his


-10-





saltwater counterpart can do little to his saltwater except carefully

choose his lease site based on rainfall data, freshwater drainage

patterns, known salinities and species preference.

Bottom samples of water in depths exceeding four feet are always

checked for salinity stratification between a lighter, fresher surface

layer and a heavier, saltier bottom layer. Surface salinity determina-

tions alone may result in the choice of bottom sites where salinities

are high enough to harbor marine predators or lead to the rejection of

suitable bottoms where salinities are actually favorable to oysters.

Ocean salinity is 35-36 o/oo (parts per thousand salt). Near oceanic

salinity is best for the hardshell clam which does not tolerate salini-

ties under 20 o/oo. The oyster has a wider range of salinity tolerance

but it does best where river water and freshwater effluents (vitamins,

nutrients, etc.) are well mixed with ocean water and where the salinity

is low enough to discourage predators and diseases with marine affinities

but still high enough to give the oyster a pleasing salty taste. Zones

of optimum salinities change year to year with rainfall totals and

distribution but a general criterion to follow is to choose sites that

register no more than 30 o/oo during the dry season or less than 8 o/oo

during the rainy season. The best oysters usually come from areas of

small or gradual salinity variations. Of course, salinity determinations

made in years of extreme drouth or rainfall make long-range recommenda-

tions for lease sitesprecarious. Less is known about the optimal

salinity requirements for the Rangia clam, particularly for its upper

ranges. Generally, it seems to thrive best in waters that change from

fresh (o/oo) to brackish from wet to dry season. Rangia clams taste

best from saltier waters, however.

Large canals draining raw upland, creating waterfront real estate and

emptying into the Peace River, Myakka River and Alligator Bay have

-11-





resulted in salinities that change more rapidly and go lower tha.i when

freshwater seeped slowly through pine flatlands, marshes add mangrove

swamps into Charlotte Harbor. Attached animals such as the oyster cannot

escape abruptly decreased salinities* They die or deteriorate from

enormous metabolic regulatory problems.

Water temperatures conducive to yearly spawning of the eastern

oyster are never a limiting factor in Florida. Minimum spawning temper-

atures from 60-680F. are common even in winter and optimum spawning

temperatures from 80.5-82.56F. are reached in late spring when shell

plantings for cultch are recommended. Some northern areas fail to have

oyster reproduction because of cold water in spring and summer. Colder

winters with lowered water temperatures are more conducive to oysters

"fattening" up than warm winters. This "fattening" is actually the

storage of glycogen, animal starch.

The combined Peace and Myakka Rivers are one of the major drainage

basins of Florida with a total watershed of approximately 2500 square

miles. Because of this, Charlotte Harbor is one of the major estuaries

where freshwater and ocean water mix but tidal ranges are not great

enough to get any drastic differences in salinities between high and

low tides.

Initial hydrographic stations were made on June 5 in Charlotte

Harbor, Myakka River and Peace River before a bad drouth was broken by

summer rain. For quick reference, the salinities of June 5 and other

representative ones have been charted on Map. 3. All salinities, temper-

tures and related data for the stations located on Map 2 are given in

Table 3. Seven salinities at correlative stations made during a rainy

period and year (1960) are charted on Map 4 for comparison. Rainfall

for seven months preceding the September 1960 sampling totaled 40.44

inches, for seven months preceding June 1962 only 6.24 inches.Resulting

differences in salinities are extreme. They are discussed in the

sections on bodies of water. -12-








.1 I


Scale: 1" = 250,000"


Map 2
Location of hydrographic stations made in Charlotte
County and vicinity (June 5-21, 1962; see Tabe 3)


-13-


FSBCML NO.: 62-12
CS No,: 62-1


/
/



j7
/
/
/
/


,)
LO /


- 11







Scale: 1" w 250,r000"


<12*


- (6')
K<1,


<1,0
---.(10


7.7
-=0 (


3 7 6


6.0(4.
36.0


352(a201)
35.0



35.0


37015).(121)
33.55
Map 3
Representative water salinities (su-face o'/) and depths (ft.) in
bottom o/oo
Charlotte County and vicinity (June 1962)
FSBCML NO. 68-12
CS NO.: 62-1
-14-







Scale: 1" = 250,0004'


,30.5
30.5"


22.1- -
22,1


Map 4

Water salinities (su 0fe o0o0) and depth (ft.) taken in
bottom o S1oo
Charlotte County (September 1960)
FPDCML NO.: 62-12
CS NO.: 62-1


-15-


z S 4,,


4.









Table 3

Hydrographic data for stations located on Map 2


STATION DATE TIME TIDE MOON WATER DEPTH BOTTOM
PHASE "C. o/oo (ft.)


1. VI- 5-62 0850 SL NM 29.2 37.5 36 hard
36.5 sand

2. 0915 SL NM 29.2 36.5 12 hard
36.0 sand

3. 0930 SL NM 28.1 35.5 12 hard
35, 8 sand

4. 0950 SL NM 28,0 35.0 20 hard
35.,0 mud

5. 1000 SL NM 28.3 33.0 13 hard
33.5 mud

6. 1020 SL NM 28.3 31.4 12 soft
30.9 mud

7. 1045 SL NM 28.3 28.4 18 sandy
28.9 mud


7.


7.


8.


9.


10.


10.


11.


VI- 7-62


VI-21-62


VI- 5-62









VI-16-62


VI- 5-62


1100


1030


1055


1100


1115


1230


1155


SH


SL


SL


SL


F


FQ


FM


NM


NM


NM


FQ


NM


30.0


28.7


28.2


29.5


30.1


29.8


30.2


28.6
29.5

19.3
23.3_

23.2
22.0

22.8
22.9

15.5
17.6

13.0
11.6

<1.0
<1.0


18


18


12


8


8


10


6


sandy
mud

sandy
mud

mud


mud


mud


mud


mud


-16-


__1


II






~






~


-


I






I


I"









Table 3

(continued)

Hydrographic data for stations located on Map 2


STATION DATE



12 VI- 5-62



13. "



13. VI- 6-62



13. VI-21-62


14. VI- 5-62



14. VI- 6-62



15. VI- 5-62



15. VI- 6-62



16. vi- 5-62



17. "


18. VI- 6-62



19. VI- 7-62



20, VI- 8-62



21.


TIME TIDE MOON WATER DEPTH BOTTOM
PHASE o.C .nn (ft.)

1400 F NM 32.0 32.5 12 hard
32.5 mud


1420



0920



0945



1430



1015



1440



1250



1500



1515


1430



1500


0900


1000


F



SL



SH


F



SL



F


F



F



F



F



F



SH


SH


NM



NM



FM



NM



NM



NM



NM



NM



NM


NM



FQ



FQ


FQ


32.0



29.2



28.5


32.0



28.0



30.0



32.0



30.0



30.0


31.8



32.0



29.2



30.0


29.4
31,0

27,3
28.4

14.2
14.5

22.7
23*2

16.2
17.3

13.0
17.6

8.8
10.0

7.7
8.8

<1,0
<1.0

27.9
29.0

25.5
25.5

31.4
31.4

36.0
35.5


10



8



9


8



8



6


6



7


10



15


2



10


6


sandy
mud

sandy
mud

sandy
mud

sandy
mud

sandy
mud

sandy
mud

sandy
mud

mud



mud


mud



soft
mud

mud


mud and
vock


-17-


_ ____~__~_ ___ ____ _IT__~__I _____ __


____ __


___~_


Ir


--



~~_


-- -










__



--- --



--


I



r


I



e






I



I






rr


rr~










--



~-r


-- -


I-



-*II










rr.



u


rrr



rr








Table 3

(continued)

Hydrographic data for stations located on Map 2


STATION DATE TIME TIDE MOON WATER DEPTH BOTTOM
PHASE 0C. o/oo (ft.)

22 VI- 8-62 1045 SH FQ 32.0 25.3 6 sandy
24.0 mud


VI-21-62


VI-12-62


it


23,


23.


24.


25.


26.


27.


28.


VI-13-62






VI-14.-62


'i


0920


1200


1330


1700


1745


1015


1030


SH


SH


SH


E


E


SL


SL


FM


FM


FM


FM


FM


FM


FM


28.0


29.1


29.1


29.9


29.8


28.8


29.1


<1.0
12.6

34.5
34.5

26.3
26,3

17.1
17.1

34.5
36.5

36.5
36.5

35.0
15O


2


2


2


6


3


sandy
mud

mud


mud


mud and
rock

sandy
mud

sandy
mud

sandy
mud


29. 1100 F FM 29.1 34.5 2 sandy
34.5 .mud

30. 1200 F FM 30.2 35.0 2 shell
35.0

31. 1230 F FM 31.0 35.4 5 sandy
35,4 mud

32. 1310 F FM 31.0 35.0 5 shell
35.0

33. 1345 F FM 30.9 34.5 6 shell
35.5

33. VI-21-62 1110 SH FM 29.0 33.6 7 shell
33.6


-18-


1.


I,













--


__


I


I


It












Hydrographic


STATION DATE TIME


Table 3

(contionted)

data for stations located on Map


TIDE MOON WATER
PHASE oC. o/oo


2


DEPTH BOTTOM
(ft,)


34. VI-16-62 1155 F FM 29.1 32.7 11 sand &
32.7 shell

34. VI-21-62 1130 SH FM 29.0 32.4 6 sand &
33.0 shell
, t ,


-62 1205


-62 0900


" 0945


" 1030


" 1110


" 1215


" 1310


-62 1330


" 1350


F FM


F FM


F FM


F FM


F FM


F FM


SH FM


Tidess E = Ebb
SL = Slack Low
F m Flood
SH = Slack High


VI-16


VI-20


35.


36.


37.


38.


39.


40.


41.


41.


42.


28.8


30.8


31.0


31.7


31.2


31.2


31.4
31,4


29.8


29.6


7.2
26.3

36.0
36,0

35.5
35.5

34.6
34.6

35.5
35.5

34.6
34.6

21.2
22.0

2200
22.3
22,3

8.2
8,2


4


8


2


10


7


6


6


mud


sandy
mud

sandy
mud

sandy
mud

sandy
mud

sandy
mud

mud


mud


mud


VI-21


_
- --


. . I I ll


IL


I








BODIES OF WATER
(see Map 1)

Stations referred to in the following discussions are located on

Map 2 and listed in Table 3.

Peace River:

Oyster growth and condition were disappointing on concrete pilings

at the Punta Gorda highway bridge and the old bridge now used for fish-

ing. Slime and barnacles covered flat oysters of non-marketable sizes.

After summer rains began, salinity dropped from 29.4 to 14.2 at the

bridge with no significant stratification between surface and bottom

samples; in September 1960 shortly after hurricane Donna, the water was

fresh (<1.0 o/oo), As mentioned earlier, 40.44 inches of rainfall in

seven months preceded the 1960 readings and only 6.24 the 1962 readings.

Dense concentrations of Rangia clams were found at Long Island and

Harbor Heights and between these two locations wherever a soft muddy

bottom and black rush (Juncus roemerianus) prevail. Rangia clams are

present from Long Island to the legal freshwater line (Station 16) where

a tidal interface was observed. These clams were salty tasting during

the drouth but lost their tang after summer rains lowered salinities.

Pollution control is vital if Rangia clams from the Peace River are

to be successfully exploited commercially. In the past effluents from

phosphate fertilizer plants have been a problem. Additionally, septic

tank discharges into the river during the summer rainy season must be

considered.
Alligator Bay

The best oysters found during the field survey for this report were

in this small, mangrove-lined bay. They were cupped, clean, good tasting


-20-








3 1/2 to 6 inches long. The oysters are mostly around mangroves and o..

a soft, mud bottom. Crown conchs, the most common oyster predator in

south Florida, are scarce or absent. Salinities were 27.9-29.0 o/oo

(Station 18); in September 1960, 6.8 o/oo.

The fate of this area for continued quality oysters rests with

future:real estate development. If Port Charlotte expands to change the

mangrove zones into waterfront real estate by dredging and filling, shell-

fish potential is questionable. Oyster leases have been applied for at

the mouth of Alligator Bay.


Myakka Cutoff:

Most oysters examined were narrow and flat. Mud bottoms predominate.

The shorelines are dominated by red mangroves with some cordgrass. Good

oysters are reputed to come from this area on the Alligator Bay side

during certain winters.


Tippecanoe Bay:

Fat cup oysters were discovered at the head of the bay. These were

3 1/2 to 4 1/2 inches long and on a soft mud bottom. They were in bars

near;mangroves and also in open water. Few oysters were actually grow-

ing on prop roots of red mangroves. Oysters opened were in good condi-

tion and tasty but somewhat muddy. This small bay should be good for

oyster leases. There is access to its shoreline by road where oysters

could be loaded on trucks or a shucking house could be located.


Myakka River:

There is a good set of oysters from the water surface to bottom on

pilings of the El Jobean railroad bridge. These oysters were in good

condition except for fouling organisms on the shells. Oyster set was







much less on the new highway bridge parallel with the railroad brid.e.

El Jobean is a key salinity station (Station 7) like the Punta Gor-da

bridge across Peace River. After summer rains began, the salinity

dropped but did not begin to approach that of September 1960 when the

river was completely fresh. Broken submerged pilings make oyster tong-

ing difficult under the railroad bridge. This station usually should

have good oysters during drouth years. No crown conchs were seen.

Scattered oysters are found north of El Jobean but there pp atred

to be none of any commercial quantity or marketable quality.

The Rangia marsh clam is distributed from about two miles north of

the El Jobean bridges to two miles north of the bridge across Highway

U. S. 41, Densest concentrations are found from Bird Island to Tarpon

Point wherever black rush dominated the shoreline and soft mud the

bottom as in Rangia beds in Peace River.

Alligator Creek (Located south of Punta Gorda):

Drainage canals creating waterfront property have been cut into the

north and south forks of Alligator Creek. Rock has been exposed along

the canal edges where oysters have set and reached marketable size and

quality but oyster shells are brittle contrasted with those in natural

watercourses. The same brittleness has been noted before in Pirate

Harbor under similar conditions. The effect of summer rains on salinity

and stratification showed up well at Station 22 where surface readings

dropped 24.3 o/oo and bottom readings 11.4 o/oo (see Table 3) in 13 days.

Pirate Harbor:

Salinities were very high (oceanic actually) compared to
in September 1960. Fat oysters six to eight inches long were harvested

from here in the winter of 1960-61. This year oysters have done poorly


-22-






and most have died including ones that Officer King transplanted from

Turtle Bay. Young oysters were also dead. Shells were badly fouled by

mussels. Those oysters still living had a very salty taste.


Cape Haze Bay:

This small bay was checked because its protected water would offer

calm harvesting during northwesterly winds that occur in winter. Only

'coon oysters were found and these confined to mangrove margins* Crown

conch egg cases were present.


Trout Creek4

Only tcoon oysters attached to mangrove roots were found. Good

quality oysters have been reported in other years but their absence

here while being found in Tippecanoe and Alligator Bays is difficult

to explain.


Charlotte Harbor:

Oysters of marketable size and quality seem to be missing from this

large estuary. Hydrographic conditions should be favorable for oysters

from the confluence of Myakka and Peace Rivers south to Cape Haze Bay.

The lack of suitable bottom materials (rock,planted cultch) is probably

the limiting factor. One oldtimer reported a deepwater bar northwest

of Pirate Harbor in former years but there is no evidence of it now.

Upper Charlotte Harbor would merit some experimental cultch planting

to substantiate oyster culture potential. Any plantings, public or

private, would be best off the Cape Haze peninsula where they would be

in the lee of northwesterlies during the winter harvesting season.

Turtle Bay:

This bay and Bull Bay are the scenes of most oyster lease activity

in Charlotte County. When sampled, salinities decreased from oceanic to


-23-







about one-half that of seawater from lower to upper Turtle B.y. One

large public oyster bar lies at the mouth of Turtle Bay. Oyster growth

and quality are best along the north or deep water side of this bar.

Only *coon oysters growing on or near red mangroves were found in upper

Turtle Bay and these were scarce. Mud overlying rock typifies most of

the upper bay bottom. Rock becomes exposed toward the head of the bay.

Crown conchs are plentiful especially near the mouth of the bay. A

moderate set of young oysters was observed on shell cultch planted two

months before this survey. Shell for cultch was being planted during

this survey by blowing it off a small barge with water pressure.

The shell was being mounded in rows on a grassy bottom. Screened

rack culture of seed oysters is being tried to control predations by

conchs.

Bull Bay:

'Coon oysters are abundant near mangrove islands. One public bar

in open water near a red mangrove tuft has been heavily harvested. Most

oysters were heavily fouled by barnacles. Dense tunicate (sea squirt)

growth indicated prevailing high salinities. Crown conchs and their egg

cases are abundant.

Catfish Creek:

Sea urchins (pincushions) and crown conch eggs were abundant and

a sign of prevailing high salinities. #Coon oysters covered by barnacles

predominated. One submerged open water bar about one-third up Catfish

Creek had a few commercial quality oysters. This 'coon oyster area would

be a good source of seed for leases.


Coral Creek:

A dense set of oysters, mostly $coon but some cupped were attached


-24-






to pilings of the railroad bridge. Oyster set was much less at the

highway bridge. The upper end of Coral Creek is dammed to provide fresh-

water reservoir for the Cape Haze development. Coral Creek could be

another source of seed oysters for leases.


Gasparilla Sound:

Twelve spoil banks will be placed east of the intracoastal waterway

route which runs the length of Gasparilla Sound. Hardshell clams are

most concentrated along the inside of Gasparilla Island wherever a firm,

sticky mud bottom with seagrass is found. Most of the clams are west of

the waterway route on shoals where hand harvesting has been productive

but there are probably enough in the deeper water with a sand bottom to

justify mechanical dredging when waterway dredging is imminent.

The Grouper Hole, a small embayment formed by a mangrove projection

of Gasparilla Island, supports one of the best hardshell clam beds in

Florida. Hundredaof bushels of clams have been taken from its muddy,

grassy bottom by tonging in recent months and there are still many clams

to harvest. This site was checked in February 1961 during a bulkhead line

survey when large clams were growing three and four thick in many spots

with 15 to 20 clams per square yard. Thinning them out would improve

individual quality but it will be important to study long-term effects

of intensive harvesting on this clam population.

Very stunted 'coon oysters grow on top of Three Sisters reef which

has shell at least two feet thick. This crowded oyster bar lies in the

path of the waterway and is a potential source of seed and shell for

oyster leases. Most oysters found in Gasparilla Sound are around mangrove

islands especially on the mainland side where oyster seed was being

collected during this survey.


-25-







Placida Harhor:

Hardshell clams are abundant at the island side of the Placida-Boca

Grande railroad trestle but less so than farther south in Gauparilla

sound. Many clams were killed and their shells exposed in dred'i.ng and

filling the Gasparilla Island causeway approach to the new highway

bridge to Placida, Oyster set is slight on the highway bridge but be-

comes dense on the railroad trestle at the mainland end where freshwater

and upland effluents are less diluted by strictly saline waters. This

same effect, but less pronounced, was noticed at the El Jobean railroad

trestle across Myakka River. Tunicates were very common at the Placida

end of the railroad bridge.

Northerly fPmthe highway bridge, hardshell clams are found mainly

near the barrier island side of Placida Harbor with scattered quantities

found ai deeper water the waterway route follows near the mainland,

Scattered hardshell clams are found near Little Gasparilla Pass which

was badly silted by Hurricar Donna; oysters are not significant in this

area.

The Narrows (from Placida Harbor to southern Lemon Bay):

Large hardshell clams have been heavily harvested just north of

the Cape Haze development bridge at the widest part of the Narrows.

Clams are still abundant. Oysters, mostly coon, are limited to the red

mangrove margins. This is primarily a tonging area because water depths

average about 5 ft. M.L.W, Dredging of the intracoastal waterway will

probably do more proportionate damage to shellfish in this narrow section

than anywhere else because of this narrowness and of the restricted tidal

flushing of silt that can be expected. Water turbidity was great during

the study. A narrow dredge cut has been made northerly to Lemon Bay for

navigational purposes. Salinities were near-oceanic and bottoms predom-
-26-






inantly sand mud with attached seagrass.


Lemon Bay:

This bay has been noted along the Florida Gulf coast for its hard-

shell clams and oysters. During the survey, six boats with 10 hand-

clammers were working productive clam beds. south of Stump Pass on the

barrier island side of the bay. Clams are found from Stump Pass north

to the Englewood Beach bridge in the shallow seagrass beds also on the

barrier island side. *Coon oysters are plentiful near mangroves at the

mouths of Gottfried Creek and several smaller creeks that flow into

Lemon Bay on the mainland side.

Hardshell clams are;tound in water five to eight feet deep north of

the Englewood Beach bridge. These have been heavily tonged in recent

months. Clams are also present in shoals north of the bridge but not in

such dense concentrations as farther south where freshwater flow is not

prominent during the rainy season.

A large oyster bar with commercial quality oysters but also many

dead one lies about 300 yards southwest of the Lemon Bay Fisheries

Company at Englewood. This bar is mostly subtidal. It had the best

oysters found besides those in Tippecanoe and Alligator Bays. *Coon

oyster bars with many dead oysters were found along the mainland side of

the bay at a mangrove point midway between Englewood and Forked Creek

and at Forked Creek. These bars would probably have marketable oysters

in the deeper water around their peripheries in years with adequate

rainfall. 'Coon oysters and some cupped three-inch oysters were attached

to pilings of the Manasota Key bridge where salinities had decreased to

22.0 o/oo from near-oceanic in lower Lemon Bay. Many more oysters were

living in the reduced salinity. One more hydrographic station (42) was

made;at the head of Lemon Bay where the salinity was less than one-

-27-







fourth oceanic.

The intracoastal waterway alignment proceeds through approximately

the middle of Lemon Bay north of the Englewood Beach bridge where the

bay narrows and clams and marketable oysters lie in the path of dredging.

South of the Englewood Beach bridge, the waterway alignment lies east

of commercial clam beds but most spoiling will be west of the waterway

route on mangrove islands or in open water.


CONCLUSIONS

Because of a bad drouth preceding field investigations for this

report water salinities in clam and oyster habitats were abnormally high,

Several locations that were fresh (<1.0 o/oo) in September 1960 had

readings near that of full strength seawater.

The Peace River bridge at Punta Gorda and the Myakka River bridge at

El Jobean are two of the most strategic spots in checking salinities for

stratification and the influence of upland watershed and freshwater flow

into an estuary (Charlotte Harbor).

The best quality oysters of marketable size found during this

survey were in Alligator Bay, Tippecanoe Bay, Lemon Bay near Englewood

and Alligator Creek.

More young oysters were alive in those areas where freshwater con-

centration can discourage marine predators and diseases such as apper

Lemon Bay, Coral Creek and Myakka River at El Jobean.

The crown conch, locally the most important oyster predator was

observed to be the most abundant in Bull Bay and Turtle Bay. The two

bays are eenterof oyster lease and culture activities.

Heavily populated beds of Rangia marsh clams in the Peace and Myakka

Rivers could probably support a commercial fishery if processing proves

economically feasible, marketing outlets develop and sources of river

-28-







pollution are controlled.

Rangia clams seem to do best where the freshwater-brackish water

zone shifts back and forth from rain to drouth.

Hardshell clams are most plentiful on the Gulf side of Gasparilla

Sound, Placida Harbor andsouthern Lemon Bay where seagrasses grow on

soft, sticky, sandy mud bottoms along the barrier islands. These clam

concentrations lie west of the intracoastal waterway alignment and are

shallow enough for hand digging or tonging.

Less dense concentrations of hardshell clams are found in deeper

water on harder, sandier bottoms in Gasparilla Sound and Placida Harbor.

These areas would be most affected by dredging and spoiling for the

waterway. Oysters involved are mostly Icoon but suitable for seeding

leases.

Commercial hardshell clams would be most affected by the intra-

coastal waterway development in the Narrows between Placida Harbor, where

large clams are plentiful and Icoon and some cup oysters lie along the

mangrove shoreline, and in Lemon Bay in deeper water (six to eight feet)

just north of the Englewood Beach bridge. The only oyster bar with

significant commercial quantity and quality of oysters subject to the

effects of waterway development was in Lemon Bay off Englewood.




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