NEW PERMANENT COHO, ALEWIFE EXHIBIT 

 OPENS IN HALL OF FISHES 



A new permanent exhibit opening Au- 

 gust 1 in the Hall of Fishes features two 

 of the most prominent fishes found in 

 Lake Michigan, the Coho salmon {On- 

 corhynchus kisutch) and the alewife (Alosa 

 pseudoharengus) . 



The growth stages in the three-year 

 life cycle of the Coho salmon will be 

 depicted including two models of the 

 adult male fish to show the different 

 coloring pattern in the breeding male. 



The Coho salmon, a native of the 

 Pacific Coast area, was raised in hatch- 

 eries in Michigan and released in 1966 

 into streams which feed in Lake Mich- 

 igan. Since then, the Coho salmon has 

 established itself well and has become 

 a favorite of sport fishermen. This spe- 



Taxidermist Carl W. Cotton prepares a model 

 of an alewife for the new exhibit in Hall N. 



August hours: 9 a.m. to 6 p.m., Monday, 

 CALENDAR OF EVENTS Tuesday and Thursday; 9a.m. to 8p.m., 



Wednesday, Friday, Saturday and Sunday. 



August 1 Thursd.w Film Series for Children Final film in a series of four 

 movies shown free to youngsters. "Life All Around Us," will be shown at 

 10 a.m. and 1 p.m. in the James Simpson Theatre. 



Through August 15 M.\s.\d.^, King Herod's Fortress Special exhibit of his- 

 torical data and archaeological treasures from the 1963-65 excavations at 

 Masada, led by Yigael Yadin. The Museum's largest special exhibit in several 

 years includes scrolls found in the caves of Bar-Kokhbar on the western shore 

 of the Dead Sea in Israel. Museum members and their families admitted free; 

 Xon-members admission, 75 cents for adults, 35 cents for children. Free 

 film on Masada shown daily at 10:30 a.m. and 2:30 p m. in the Lecture Hall. 



Through September 16 C.AMOUFL.JkCE in N.-vture Photographic exhibit in color 

 by Edward S. Ross, an entomologist, demonstrates a variety of ways in which 

 living things are protected by coloration. Three-dimensional Museum ex- 

 hibits supplement the photographs. Hall 9 Gallery. 



Continuing in August Egypt Through .\ Biologist's Eye Photographic ex- 

 hibit by Dale J. Osborn, Field Associate in Zoology. Moved to Hall J. 



Through August 31 Field Museum Gener.\l Highlights Tour Free public 

 tour of the Museum, conducted by the Raymond Foundation. Tour is fol- 

 lowed by a film, "Through These Doors." Tour begins at 2 p.m., Monday 

 through Friday. Film will be shown at 3 p.m. in the Lecture Hall. 



Through August Summer Journey : The Fishes of Lake Michig.\n A do-it-your- 

 self tour for youngsters which will acquaint them with some of the residents of 

 Lake Michigan. Sponsored by the Raymond Foundation. Any child who 

 can read and write may participate in the Journey Program. Free Journey 

 sheets are available at the North and South Doors and the Information Desk. 



Half A Billion Years of Illinois History Do-it-yourself tour for Museum vis- 

 itors in observance of the state's Sesquicentennial celebration covers aspects of 

 anthropology, botany, geology and zoology. A free brochure, available in 

 Stanley Field Hall, provides a guide to pertinent exhibits. 



cies may grow to a length of 32 or 33 

 inches and weigh up to 25 pounds. 



The Coho salmon remains near shore 

 during the spring but moves into deeper 

 parts of the lake during the summer. 

 In the fall of its third year, the fish 

 moves inshore again and then goes up 

 streams to spawn. 



This predator feeds on many fishes 

 in the lake, including alewives. 



The alewife, a native of the Atlantic 

 Coast, probably migrated to Lake Mich- 

 igan through the other Great Lakes. 

 It appeared in Lake Michigan about 

 20 years ago and has flourished. 



Here the alewife has a three-year life 

 cycle, although in its Adantic Coast hab- 

 itat it may live from five to seven years. 



Toward the end of their life cycle, 

 the alewives come close to the shore to 

 spawn, usually in the late spring and 

 early summer. The heaps of dead ale- 

 wives which have been notorious on 

 some beaches and shorelines occur at 

 the time of this inshore migration. The 

 alewives who spawn in July die some- 

 time later, probably during the winter. 



The newly hatched alewives remain 

 close to shore until the autumn after 

 they are spawned. They feed on plank- 

 ton which they strain from the water 

 with very efficient "gill traps." When 

 they are older they move into the mid- 

 waters of the lake where they eat a type 

 of small crustacean and the larvae of 

 other fishes. 



Alewives also have some commercial 

 value. More than 50 million pounds 

 of these fish were caught and processed 

 for pet food last year. 



Both the alewife and the Coho sal- 

 mon are 'success stories" in terms of 

 the Lake Michigan habitat. The brief 

 life spans are indicative of the high rate 

 of survival of the young of these two 

 species. 



FIELD MUSEUM 



OF NATURAL HISTORY 



ROOSEVEI.T ROAD AT LAKE SHORE DRIVE 

 CHICAGO. ILLINOIS S0«09 A.C. 312. 922-94t0 

 FOUNDED BY MARSHALL FIELD. 1893 



E. Leland Webber, Director 



BULLETIN 



Edward G. Nash, Managing Editor 



Pages AUGUST 



PRINTED BY FIELD MUSEUM PRESS 



