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Then tag number 064, consisting of two kelly-green discs fastened to the shrimp by a nickel pin, came into the hands of a Marine Laboratory biologist. The tagged shrimp, which had been free 123 days, was caught on the fishing grounds 62 miles in a straight line from where it had been tagged in Coot Bay, a few miles north of Flamingo.

The shrimp, one of about 1,000 tagged in the Park area, had grown about 1-5 inches during the four months at large. This is an increase from about 100 "count" to 36 "count" in fishermen's language, meaning that it would have taken about 100 tails of shrimp the size it was when tagged to make a pound and only about 36 at the time of its capture to make a pound.

In addition to this tagging program, which is part of the research being conducted by the Marine Laboratory on the shrimp fishery for the Florida State Board of Conservation, shrimp have been tagged in the commercial fishery and returns have been surprisingly good. Between 25 and 30 percent of all tagged shrimp released have been captured a second time. The valuable information obtained on migrations and growth of the shrimp will eventually help conserve this great resource.

Fur-Seal Prices Advance at Government Spring Auction

An average advance of 8.9 percent in prices paid at the semiannual auction of Government-owned fur-seal skins marked the spring sale held in St. Louis on June 7. A total of 25,386 skins, products of the sealing industry administered by the Department of the Interior's Bureau of Commercial Fisheries on the Pribilof Islands of of Alaska, brought $1,809,272. This compares with 28,782 skins sold for $1,983,208 at the October 1957 sale. The average for all skins sold for the account of the United States Government at the June 7 sale was $71.27; the average at the October 1957 auction was $68.90.

The Alaska skins included 7,568 black, 14,221 dyed "Matara" (brown), and 3,597 of the newest shade called "Kitovi." The black skins sold at an average of $81.04; Mataras at $67.84; and Kitovis at $64.26.

In addition to the United States skins, 11,324 South Africa fur-seal skins were sold for private shippers and the account of the Government of South Africa at an average of $26.60, an advance of 3.4 percent; 500 Uruguay fur-seal skins were sold for the Government of Uruguay at an average of $26.36.

The auction held at the show rooms of the Fouke Fur Company in St. Louis, Mo., normally set for April, was delayed because of a labor-management dispute at the Fouke plant.

NOTE: SEE COMMERCIAL FISHERIES REVIEW, DECEMBER 1957, P. 21.

Great Lakes Fishery Investigations

FIELD TEST OF CHEMICAL FOR KILLING YOUNG SEA LAMPREY SUCCESSFUL: A successful field test of a chemical found effective in destroying young sea lamprey without harming fish was carried out on May 14, 1958, at Mosquito Creek, a well known rainbow trout stream flowing into Lake Superior about 15 miles east of Munising, Mich. The action of this particular chemical, one of several being investigated, had not previously been studied under stream conditions.

The chemical was fed into the stream above the areas infested with the parasite for eight hours. Young lamprey held in cages in the stream showed the effects of treatment within an hour and were all dead after seven hours of exposure. Lamprey in the stream were similarly affected and sampling crews found many dead, but no living lamprey, following the treatment.

Rainbow trout in the stream became restless, but only one casualty was observed and this a fish weakened by earlier sea lamprey attack. Several rainbow actually took anglers' lures during the treatment. Aquatic worms were killed by the chemical but the damage to insect larvae and other forms of stream life was negligible.

The test was carried out by the U. S. Bureau of Commercial Fisheries as part of the lamprey control program of the Great Lakes Fishery Commission.

Further testing will be carried out during the summer on larger streams where application will be more difficult. Should these tests continue to prove successful, the chemical technique will assume an important role in the early control of the sea lamprey which has destroyed lake trout in Lakes Michigan and Huron and is now rapidly reducing stocks of trout in Lake Superior. NOTE: ALSO SEE COMMERCIAL FISHERIES REVIEW, JUNE 1958,

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P. 29.

SURVEY OF WESTERN LAKE ERIE CONTINUED BY M/V "CISCO:" Studies on the life history of 15 important species of fish in western Lake Erie were continued by the Great Lakes Fishery Investigations research vessel Cisco. The major objective of the work by the Cisco during 1958 is to obtain as much information as possible concerning spawning habits, egg survival, hatching, fry survival, and early life history of the fish in western Lake Erie.

Cruise 1 (March 24-April 8, 1958): A record ice jam in southern Lake Huron caused a three weeks' delay in moving the Cisco from its winter base in Bay City, Mich., to Lake Erie. Thus cruise 1 was entirely eliminated and cruise 2 was late in getting started.

Cruise 2 (April 15-18): During this cruise, 4 special trawling stations, designated as "index" stations, were established. These stations will be visited several times each year to gather data that may be useful for predicting future abundance of marketable fish. The Cisco joined the Musky and an outboard motorboat in the "index" trawling operations. The "index" stations are located north of Stony Point, Mich., north of Bono, Ohio, east of South Bass Island, and east of Cedar Point, Ohio. Limnological data including water, plankton, and bottom samples were also collected at these stations.

CISCO, RESEARCH VESSEL OF THE SERVICE'S GREAT LAKES FISHERIES INVESTIGATION.

In addition to the "index" fishing, the Cisco also trawled in areas southeast of the Detroit River Light, south of Middle Sister Island, and north of Lorain. A catch of more than 5,000 smelt was made in one 10-minute drag near the Detroit River Light, but otherwise catches were generally light. Yellow perch predominated in most cases. Smelt catches were usually small because the majority of this species were in inshore spawning areas. Most of the smelt and perch taken were either in spawning condition or were freshly spent. The catches also included mooneye, white sucker, carp, emerald shiner, spottail shiner, silver chub, channel catfish, brindled madtom, burbot, trout-perch, white bass, walleye, blue pike, johnny darter, logperch, and sheepshead. The mature walleye were ripe or nearly so. Emerald shiners were the only species found off the bottom in any numbers. They were, in fact, apparently more numerous near the surface than near the bottom. A small plankton net attached to the trawl took no fish larvae.

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A moderate degree of thermal stratification which had developed in the western basin of Lake Erie was broken up by high winds toward the end of cruise 2. Surface temperatures ranged from 6.2° C. to 13.7° C. (43.20 F. to 56.70 F.), except for somewhat higher temperatures at the mouth of the Raisin River.

Only common names will be used in the cruise reports. The following are common and scientific names of fish that will probably be taken in Lake Erie this year:

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Scientific Names

Alosa pseudoharengus
Pomoxis nigromaculatus
Stizostedion vitreum glaucum
Noturus miurus
Ictalurus nebulosus
Lota lota

Cyprinus carpio
Ictalurus punctatus
Percina copelandi
Leucichthys artedi
Notropis atherinoides
Dorosoma cepedianum
Carassius auratus
Etheostoma nigrum
Acipenser fulvescens
Percina caprodes
Hiodon tergisus
Ambloplites rupestris
Ammocrypta pellucida
Aplodinotus grunniens
Hybopsis storeriana
Cottus cognatus
Micropterus dolomieui
Osmerus mordax

Cottus ricei

Notropis hudsonius
Noturus flavus

Percopsis omiscomaycus
Stizostedion vitreum vitreum
Roccus chrysops

Pomoxis annularis
Coregonus clupe aformis
Catostomus commersoni
Perca flavescens

Cruise 3 (May 6-19): Regular trawling stations in western Lake Erie east of South Bass Island, south of Rattlesnake Island, northwest of Pelee Island, south of Kingsville (Ontario), southeast and southwest of the Detroit River light, northeast of Monroe (Michigan), southwest of West Sister Island, south of Middle Sister Island, east of Sandusky (Ohio), and north of Lorain (Ohio), were visited during cruise 3. Tows will be repeated at these stations to follow changes in the distribution and composition of fish stocks. Limited trawling was also done in Sandusky Bay. Catches in nearly every case were predominately smelt and yellow perch. Emerald shiners, spottail shiners, and trout-perch were also taken often in large numbers. Species less common in the catches were silver chub, channel catfish, white bass, walleye, and sheepshead, and the rare species included alewife, white sucker, goldfish, carp, brown bullhead, stonecat, burbot, logperch, river darter, sauger, rock bass, white crappie (Sandusky Bay only), and northern muddler.

The majority of the mature smelt and yellow perch had spawned, but a few were still gravid or ripe. Walleyes had completed spawning. None of the other species, except a single northern muddler, appeared in a spawning condition.

Most of the smelt were in the 5- to 6-inch size range, and a sizable portion of the yellow perch ranged from 5.5 to 7.0 inches in length. Small catches of year-old smelt and yellow perch sug

gest the possibility of a poor hatch of these species in 1957, but it is too early in the season to be certain.

At the beginning of the cruise an appreciable smelt die-off (probably post-spawning mortality) was in progress. The dead and dying fish were badly fungused. By the end of the cruise, however, the mortality seemed to have run its course. The unaffected smelt showed a striking postspawning improvement in condition during the two-week pe

riod.

A few fish fry were taken in plankton nets towed at various depths alongside the boat or attached to the headrope of the trawls. The fry have not been positively identified as yet, but appeared to be smelt.

During the warm, still weather which prevailed toward the end of the cruise, the water in western Lake Erie became thermally stratified and surface water temperature rose rapidly. Surface temperatures rose from a low of 9.0° C. (48.20 F.) at the beginning of the cruise to a high of 20.00 C. (68.00 F.) at the end of the cruise.

The Cisco participated in a synoptic survey of western Lake Erie on May 13, 14, and 15. Two other vessels (the Service's M/V Musky and the and the SP-2 from the Ohio Division of Wildlife) cooperated in these surveys. Similar synoptic cruises will be repeated in midsummer and fall this year. Each vessel took surface water samples and temperatures at 2-mile intervals. Drift bottles were released at a number of points. Bathythermograph casts were made at 4-mile intervals aboard the Cisco. Analyses for total alkalinity and turbidity were made on most water samples taken by the Cisco.

Extensive meteorological observations were made. These included wind velocity and direction, wet and dry bulb temperatures, and barometric pressure. An anemometer was recently installed aboard the Cisco for accurate wind velocity readings. Weather data will be related to information collected at shore stations to determine how weather influences the lake, and the effect of the lake on weather conditions over land.

Preliminary analysis of the turbidity and total alkalinity values provides evidence that the main current of the Detroit River outflow passed between Middle Sister Island and West Sister Island on May 13 and 14. Water of considerably higher turbidity and alkalinity was encountered immediately

south of West Sister Island. This is probably Maumee River water. Some shift in currents, which appears to be associated with a shift in wind direction from NE. to NW., was noted on May 15. Detroit River water extended 2 miles below West Sister Island and Maumee River water occurred in a narrow band along the south shore.

NOTE: PREVIOUSLY DESIGNATED CRUISE NUMBERS AND THEIR RESPECTIVE DATES WILL REMAIN UNCHANGED IN ORDER TO PREVENT POSSIBLE CONFUSION AND SCHEDULE CONFLICTS AMONG AGENCIES COOPERATING IN SEVERAL FUTURE PROJECTS FOR WHICH DATES HAVE BEEN SET.

Gulf Exploratory Fishery Program

EXPLORATORY SURVEY OF SARDINE-LIKE FISHES IN GULF OF MEXICO (M/V Oregon Cruise 49): Along the west coast of Florida, from Cape San Blas to Ft. Myers Beach between the 10- and 30-fathom curves, extensive mid-water schools were located by a cruise (completed April 24, 1958) of the U. S. Bureau of Commer

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cial Fisheries vessel Oregon. Sampling of these schools with a 40-foot nylon midwater trawl caught primarily small round herring (Etrumeus teres), and lesser a

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CAPE SAN BLAS

M/V OREGON CRUISE 49 (APRIL 3-24,1958).

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but became heavily concentrated at depths of 5 to 10 fathoms immediately after sunset and remained schooled at these depths until dawn. During the dark of the moon also, large quantities of these fish, attracted to a 1,000-watt light shortly after sunset, would remain all night and begin milling shortly before dawn. These were sampled with a lampara net and found to be composed of the same species as the midwater trawl catches.

The last three days of the cruise were spent surveying between Pensacola and the Mississippi Delta, in depths of 5 to 20 fathoms. Small anchovies were found in 7 fathoms off the north end of Chandeleur Island. Razorbellies (Harengula pensacolae) which were abundant in this area during February and March were not located on this cruise.

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pounds of snapper and 700 pounds of grouper were caught with the trawl in this area. The best individual tow caught 870 pounds of snapper and 50 pounds of grouper. Trawling in the area east of the Triangles resulted in 2 snapper catches of 245 and 248 pounds. Catches to the north and east across the Bank produced catches varying from zero to 100 pounds. The average tow ran 1 to 2 hours, depending on bottom conditions.

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A total of 90 exploratory drags was made. A small, heavy-duty, New England-style fish trawl was used on 81 drags. In spite of several hang-ups on rocks, there was no serious gear damage during the entire trip. The net had a 52-foot headrope and 72-foot footrope, and was made of" diameter braided nylon twine, 41" stretched mesh in the body, and 5" stretched mesh in the cod end. The footrope was rigged its entire length with 20" diameter rollers and 38 trawl plane floats were spaced along the headrope. Eight-foot bracket doors were fished 10 fathoms ahead of the wings. Towing was carried on at half speed due to the small size of the net.

The performance of the otter-trawl gear was considered to be excellent, with only occasional slight tears in the netting. It was found that with the exception of scattered high "peaks" which can uaually be avoided, the red snapper grounds of Campeche are, for the most part, trawlable with this type of gear.

FIG. 2 A CATCH OF RED SNAPPER AND SOME GROUP-
ER IN THE COD END OF THE TRAWLING NET, WHICH
IS BEING HOISTED ABOARD THE EXPLORATORY FISH-
ING VESSEL SILVER BAY. THE VESSEL WAS FISHING
ON CAMPECHE BANK.

During the trip, 9 experimental snapper traps were set, but only 1 was successful. In this case, the trap took 13 red snapper (about 2 pounds each) after 2 days in Table 1 - Weight Tabulation of Snapper and Grouper Catch by M/V Silver Bay Cruise 8

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NOTE: FOR THE MOST PART, MINIMUM SIZES OF SNAPPER CAUGHT WITH THE 5" STRETCHED MESH COD END WERE TO 1 POUND.
THE NUMEROUS SMALLER FISH WERE CAUGHT WHEN A 2" STRETCHED MESH LINER WAS USED FOR SAMPLING PURPOSES.

in the water. Another trap caught a 12-pound grouper after the same length of time.

One set was made with a sink gill net. The net was fished on the bottom for 24 hours and caught one 3-pound lane snapper, but had been badly fouled by a 12-foot tiger shark and a 150-pound sting ray.

The total snapper catch of 5,542 pounds was comprised of 10 species, with red snapper and lane snapper accounting for approxi

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