Title Page--------------------------------------------------------------  1
Copyright Page----------------------------------------------------------  2
Abstract----------------------------------------------------------------  3
Preface-----------------------------------------------------------------  4
Acknowledgments---------------------------------------------------------  4
Table of Contents-------------------------------------------------------  5
List of Tables----------------------------------------------------------  6
List of Figures---------------------------------------------------------  7
Conventions Used in this Monograph--------------------------------------  8


Chapter
    1.  Chronology of the Cormorant Harassment Issue--------------------  9
      1-A.  INTRODUCTION------------------------------------------------- 9
      1-B.  HISTORICAL CONTROL OF FISH-EATING PREDATORS------------------ 9
      1-C.  LEGAL REQUIREMENTS FOR CORMORANT CONTROL IN OREGON-----------10
      1-D.  1985 AND 1988 ADC INVOLVEMENT IN CORMORANT HARASSMENT--------10
      1-E.  1985 AND 1988 STEP INVOLVEMENT IN CORMORANT HARASSMENT-------11
      1-F.  1988 CORMORANT HARASSMENT BY ODFW PERMITTEES-----------------12
      1-G.  28 NOVEMBER 1988 ODFW MEETING ABOUT CORMORANT HARASSMENT-----12
      1-H.  CORMORANT HARASSMENT IN 1989---------------------------------13
      1-I.  OREGON HOUSE BILL 3185---------------------------------------13
      1-J.  OREGON FISH AND WILDLIFE COMMISSION--------------------------14
    2.  The Cormorant Predation Issue was Inevitable in Tillamook Co.--- 15
      2-A.  INTRODUCTION-------------------------------------------------15
      2-B.  CONFLICT AMONG FISHERMEN: A FEW COASTAL STREAM SPORTS FISHERMEN 
          FEEL THEY ARE NOT GETTING THEIR SHARE OF SALMON AND RESENT 
          PREDATORS TAKING ANY SALMON------------------------------------15
      2-C.  EMOTIONAL INVOLVEMENT OF STEP VOLUNTEERS IN RAISING SALMON---16
      2-D.  PERCEPTION THAT SALMON AND STEELHEAD RUNS ARE APPROACHING 
          RUIN-----------------------------------------------------------16
      2-E.  PERCEPTION THAT PREDATORS ARE DESTROYING SALMON AND STEELHEAD 
          RUNS-----------------------------------------------------------24
      2-F.  PERCEPTION THAT CORMORANTS ARE DESTROYING SALMON AND STEELHEAD 
          RUNS-----------------------------------------------------------24
      2-G.  PERCEPTION THAT CORMORANT HARASSMENT CAN "SAVE" SMOLTS-------30
      2-H.  "PROOF" THAT 1988 HARASSMENT WAS SUCCESSFUL------------------30
      2-I.  PERCEPTION THAT IF PREDATION IS REDUCED, THEN FISHERMEN'S 
          CATCHES WOULD INCREASE-----------------------------------------32
      2-J.  SPREAD OF PERCEPTIONS VIA NEWS MEDIA AND ANGLER'S CLUBS------34
    3.  Is Cormorant Harassment Justifiable, Economically or Otherwise?- 35
      3-A.  INTRODUCTION-------------------------------------------------35
      3-B.  CONDITIONS WHEN PREDATOR CONTROL IS JUSTIFIABLE ECONOMICALLY 
          OR OTHERWISE---------------------------------------------------35
      3-C.  ARGUMENTS FOR CORMORANT HARASSMENT IN TILLAMOOK COUNTY-------36
      3-D.  ARGUMENT AGAINST HARASSMENT: THE HARASSERS ARE PRIVATE 
          CITIZENS-------------------------------------------------------36
      3-E.  ARGUMENT AGAINST CORMORANT HARASSMENT: COMPENSATORY 
          PREDATION------------------------------------------------------36
      3-F.  ARGUMENT AGAINST CORMORANT HARASSMENT: ALTERNATIVES----------40
      3-G.  ARGUMENT AGAINST CORMORANT HARASSMENT: ECONOMIC COSTS--------40
      3-H.  ARGUMENT AGAINST CORMORANT HARASSMENT: BIOLOGICAL COSTS------41
      3-I.  ARGUMENT AGAINST CORMORANT HARASSMENT: AESTHETIC AND SOCIAL 
          COST-----------------------------------------------------------45
      3-J.  CONCLUSION: CORMORANT HARASSMENT CURRENTLY DOES NOT SATISFY 
          THE CRITERIA FOR AN ANIMAL DAMAGE CONTROL PROGRAM--------------46
    4.  Alternatives to Cormorant Harassment to Reduce Smolt Losses----- 47
      4-A.  INTRODUCTION-------------------------------------------------47
      4-B.  ALTERNATIVES TO REDUCE PREDATION THAT ARE CURRENTLY 
          PROMISING------------------------------------------------------47
      4-C.  ALTERNATIVES TO REDUCE PREDATION THAT ARE NOT CURRENTLY 
          PROMISING------------------------------------------------------51
    5.  If Done, Cormorant Harassment Should Have Guidelines------------ 52      
      5-A.  INTRODUCTION-------------------------------------------------52
      5-B.  IF DONE, CORMORANT HARASSMENT SHOULD BE DONE BY 
           PROFESSIONALS-------------------------------------------------52
      5-C.  IF DONE, CORMORANT HARASSMENT SHOULD BE LIMITED TO SPECIFIC 
          TIMES AND SITES------------------------------------------------52
      5-D.  IF THERE IS CORMORANT HARASSMENT, THERE SHOULD BE BUFFER 
          ZONES TO PROTECT NONTARGET ANIMALS-----------------------------53
    6.  Epilogue: Learning from the Cormorant Harassment Issue---------- 54
      6-A.  INTRODUCTION-------------------------------------------------54
      6-B.  VARIABLE DEFINITIONS OF WILDLIFE AND CONSERVATION------------54
      6-C.  EXAGGERATED CLAIMS CAN BE COUNTERPRODUCTIVE------------------54
      6-D.  THE ODFW's PUBLIC RELATIONS COULD BE IMPROVED----------------54
      6-E.  LEGISLATIVE DEBATE OF HOUSE BILL 3185 ABOUT CORMORANT 
          HARASSMENT-----------------------------------------------------55
      6-F.  SUCCESS OF HOUSE BILL 3185 IN OREGON HOUSE-------------------58
      6-G.  FAILURE OF HOUSE BILL 3185 IN OREGON SENATE------------------58
      6-H.  FAILURE OF BIOLOGICAL DATA TO PERSUADE LEGISLATORS: BIOLOGISTS 
          NEED TO BETTER COMMUNICATE WITH NONBIOLOGISTS------------------58
      6-I.  IS OREGON WILDLIFE OR WILDLIFE MANAGEMENT FOR SALE?----------58
      6-J.  WHEN IS PREDATION BY A SMOLT PREDATOR SIGNIFICANT?-----------59
      6-K.  CAN THERE EVER BE ENOUGH SALMON OR STEELHEAD?----------------59
      6-L.  THE CORMORANT ISSUE WILL CONTINUE IN NORTH AMERICA-----------59


Appendix 
    I.    Scientific names for common names of animals mentioned in this
            monograph--------------------------------------------------- 60
   II.    Sources of mortality for currently-raised hatchery fish------- 61
      II-A.  INTRODUCTION------------------------------------------------61
      II-B.  STAGE I MORTALITY: VULNERABILITY OF CURRENTLY RAISED HATCHERY 
          SMOLTS TO PREDATION SHORTLY AFTER RELEASE----------------------61
      II-C.  STAGE II MORTALITY: MORTALITY OF HATCHERY SMOLTS BECAUSE OF A 
          SYNERGISTIC RELATIONSHIP AMONG FOOD ABUNDANCE, INEFFICIENT 
          FEEDING, AND PREDATION-----------------------------------------61
  III.    Ocean and coastal stream catches of coho salmon--------------- 64
   IV.    Ocean and coastal stream catches of chinook salmon------------ 66
    V.    Maximum number of Brown Pelicans, Common Loons, Horned Grebes, 
            Brant, Buffleheads, and Caspian Terns censused at Yaquina 
            Estuary in April-June--------------------------------------- 68
   VI.    Maximum number of shorebirds censused at Yaquina Estuary
            in April-June----------------------------------------------- 69
  VII.    Are additional studies to study smolt predators warranted?---- 70
      VII-A.  INTRODUCTION
      VII-B.  STUDIES OF BIRD PREDATORS
      VII-C.  STUDIES OF PREDATORY FISH
VIII.    Harmful effects of hatchery salmonids on wild salmonids-------- 71
      VIII-A.  INTRODUCTION----------------------------------------------71
      VIII-B.  DEFINITION OF "WILD" FISH---------------------------------71
      VIII-C.  BENEFITS OF WILD SALMONIDS--------------------------------71
      VIII-D.  HARMFUL EFFECTS OF HATCHERY SALMONIDS---------------------71
IX.    Estimating the daily food requirements of fish-eating birds------ 73
      IX-A.  INTRODUCTION------------------------------------------------73
      IX-B.  DIGESTION CAN AFFECT PREY SIZE DETERMINATION----------------73
      IX-C.  SHOOTING BIRDS AND USING STOMACH CONTENTS-------------------73
      IX-D.  LIVE CAPTURE OF BIRDS AND USE OF STOMACH CONTENTS-----------73
      IX-E.  USING PELLETS OR FECES TO DETERMINE DAILY FOOD CONSUMPTION--74
      IX-F.  USING STOMACH CONTENTS OF BEACHED BIRDS---------------------74
      IX-G.  DIRECT OBSERVATION OF FOOD EATEN BY WILD BIRDS--------------74
      IX-H.  ESTIMATING DAILY FOOD CONSUMPTION OF WILD BIRDS FROM CAPTIVE 
          BIRDS----------------------------------------------------------74
      IX-I.  MEASURING ENERGY CONSUMPTION OF WILD BIRDS------------------75
    X.    Letter from Oregon Representative Paul Hanneman to Kathleen
            Confer------------------------------------------------------ 76
   XI.    Reprint of Hoffman and Hall's (1988) USDA Animal Damage Control 
            interoffice memorandum-------------------------------------- 77
  XII.    Copy of original House Bill 3185, as introduced in March 1989- 79
 XIII.    Copy of amended House Bill 3185------------------------------- 80
  XIV.    Reprint of Erickson's (1989e) written petition to the Oregon 
            Fish and Wildlife Commission-------------------------------- 81
   XV.    Reprint of Erickson's (1989d) written testimony to Oregon House 
            Agriculture, Forestry and Natural Resources Committee------- 82

Literature Cited-------------------------------------------------------- 84

Index------------------------------------------------------------------- 95

                              
LIST OF TABLES

Table 2.1.  Coho salmon catch by Oregon ocean commercial troll, ocean 
     sports, and coastal stream sports fishermen------------------------ 15
Table 2.2.  Size, average weight, approximate cost, estimated number, and 
     release date of ODFW salmonids released in March-June 1988 into the 
     Tillamook Basin---------------------------------------------------- 29
Table 2.3.  Estimated number of smolts/cormorant and total cost of daily 
     salmonid consumption by 300 cormorants eating salmonids released 
     into the Tillamook Basin in March-June 1988------------------------ 29
Table 2.4.  Predation of cormorants on salmonid smolts at Tillamook 
     Bay---------------------------------------------------------------- 30
Table 2.5.  Use of an electric weir, dates of counting steelhead jacks, 
     and number of steelhead jacks returning to the ODFW North Fork 
     Nehalem Fish Hatchery---------------------------------------------- 31
Table 2.6.  Number of steelhead jacks counted returning to the ODFW 
     North Fork Nehalem Fish Hatchery during the 1985-1986 and 1988-1989 
     return seasons----------------------------------------------------- 31
Table 2.7.  Differences between years in number of returning winter 
     steelhead or coho jacks released as smolts in the spring of 1987 
     or 1988------------------------------------------------------------ 32


Table 3.1.  Summary of criteria for when animal damage control 
     (including harassment) is justifiable------------------------------ 35
Table 3.2.  Marine or estuarine predators that occur in Oregon waters
     that have been observed to prey on juvenile coho or chinook-------- 37
Table 3.3.  Marine or estuarine predators that occur in Oregon waters 
     that may be predators of juvenile coho or chinook------------------ 38
Table 3.4. Predation of juvenile coho or chinook by subadult or adult
     salmonids---------------------------------------------------------- 39
Table 3.5.  Estimate of number of smolts eaten by salmonid predators 
     in 1981 along the Oregon Coast------------------------------------- 39
Table 3.6.  Selected April-June bird records for Nehalem, Tillamook, 
     and Netarts Bays--------------------------------------------------- 43
Table 3.7.  Bald Eagles and Peregrine Falcons recorded during 
     Tillamook Bay Christmas Bird Counts in December-------------------- 43
Table 3.8.  U.S. Fish and Wildlife Service aerial waterfowl censuses at 
     Nehalem, Tillamook, or Netarts Bays in April----------------------- 44
Table 3.9.  Chinook or coho salmon predation on some important fish or 
     invertebrates caught in other Oregon fisheries--------------------- 46


Table 4.1.  Contribution to ocean and Columbia River fisheries by ODFW 
     barged coho salmon smolts------------------------------------------ 48


Table 5.1.  Guidelines for cormorant harassment in Oregon estuaries----- 52

Table (Appendix) II.1.  Possible major causes of smolt mortality after 
     release------------------------------------------------------------ 63



                         
Figures

Fig. 2.1.  Sports coho catches in the Nehalem or Tillamook Basins for 
     1970-1986---------------------------------------------------------- 18
Fig. 2.2.  Oregon ocean commercial troll, ocean sports, and coastal 
     stream sports catches of coho or chinook--------------------------- 18
Fig. 2.3.  Sports fall or spring chinook catches in the Nehalem or 
     Tillamook Basins for 1970-1986------------------------------------- 19
Fig. 2.4.  Value to Oregon ocean commercial troll fishermen at landing 
     of coho and chinook catches for 1971-1988-------------------------- 19
Fig. 2.5.  Sports winter or summer steelhead catches in the Nehalem or 
     Tillamook Basins--------------------------------------------------- 20
Fig. 2.6.  Oregon coastal stream sports catches of summer or winter 
     steelhead for 1962-1985-------------------------------------------- 20
Fig. 2.7.  Number of salmon fishing trips and number of coho or chinook 
     caught per fishing trip by  Oregon ocean sports fishermen---------- 21
Fig. 2.8.  Total steelhead caught, steelhead caught/100 hours of 
     fishing, and total hours of fishing on the Alsea River Estuary for 
     the 1960-1961 through 1986-1987 fishing seasons-------------------- 22
Fig. 2.9.  Fishing effort (thousands of boat days) by Oregon ocean 
     commercial troll fishermen----------------------------------------- 23
Fig. 2.10.  Coho or chinook caught per boat day by Oregon ocean 
     commercial troll fishermen----------------------------------------- 23

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The cormorant/fisherman issue is not limited to Tillamook County in 1988-1989 but is symptomatic of a widespread conflict of some fishermen with fish-eating animals.

Predators, specifically cormorants, have been blamed for the "ruin" of the Tillamook fisheries, but the effects of cormorant predation have been exaggerated. Actually, current salmon and steelhead catches are similar to or greater than many catches prior to 1972, when several "predators" (including Double-crested Cormorants) were not protected by law. Although it is clear that cormorants can eat some smolts in Tillamook Bay, it is unreasonable to assume that they eat as many as has been suggested. For example, when figures that appeared in a Tillamook newspaper are added up, cormorants in Tillamook Bay in 1988 were suggested to eat nearly three times as many smolts as were released there!

Because a few Tillamook County fishing guides and fishermen felt that cormorants were destroying their salmon and steelhead fisheries, they pressured the Oregon Department of Fish and Wildlife (ODFW) into giving them permits to harass (but not kill) cormorants in the spring of 1988 on public waters of Nehalem and Tillamook Bays. The permittees were not supervised to be sure that they did not disturb or harm nontarget wildlife (i.e., wildlife other than the targeted cormorants) or did not kill cormorants.

After the ODFW announced in late November 1988 that they would not be issuing cormorant harassment permits in 1989, a few Tillamook fishing guides and fishermen worked to pass House Bill 3185 during the 1989 Oregon Legislative session. House Bill 3185 would have allowed cormorant harassment along the entire Oregon Coast any time during the year, but the Bill failed. Then, in July 1989, the Oregon Fish and Wildlife Commission refused to consider granting harassment permits to fishing guides and fishermen. Thus, cormorant harassment in 1989 was not legalized, although some harassment apparently occurred illegally.

Cormorant harassment in Tillamook County does not currently meet the requirements to justify an animal damage control program. For example, one criterion of such a program is that there be minimal compensatory predation (i.e., prey saved from the controlled predator is taken by noncontrolled predators). But if cormorants are harassed, there are many other predators that could eat the "saved" smolts, including adult coho and chinook salmon, steelhead, cutthroat trout, and striped bass that may eat millions of salmon and steelhead smolts along the Oregon Coast each year.

Current information indicates that documented smolt losses from cormorant predation may not compensate the economic, biological, aesthetic, and social costs of harassment. Biological costs include disturbance to nontarget wildlife such as waterfowl or threatened and endangered birds like the Bald Eagle and Brown Pelican; disturbance would unavoidably accompany cormorant harassment. One social cost of interest is that predator control of cormorants to "save" salmon is arbitrary and capricious, since salmon are themselves a significant predator of young Dungeness crabs and fish important to other Oregon commercial and sports fishermen.

Alternatives to cormorant harassment exist and would address all smolt predation, not just that by cormorants. These alternatives include changing hatchery practices, so that smolts survive better after release. These alternatives should be at least considered.

Biologists may have somewhat defused the cormorant harassment issue if they were more able to communicate with nonbiologically-trained fishermen, but even so, there are a few fishing guides and fishermen who refuse to believe any information that does not agree with their own opinions.

Keywords: Animal Damage Control, Chinook, Coho, Cormorants, Fisheries, Oregon Legislature, Predation, Predators, Salmon, Smolts, Steelhead.

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Electronic File Legend for SOO No. 6:

++++=comment lines that were not in print version 
*page=page number of original printed version (e.g., page 115=*115), so to 
     search for p. 115, search for *115.

MAJOR DIFFERENCES BETWEEN PRINT & ELECTRONIC VERSIONS.--The page width has been changed from the print version, and I have adjusted a few page breaks from the original printed version so that paragraphs are not split between pages. Line graphs in the printed version have been converted to bar graphs.

COMMENTS ABOUT SOO No. 6 (January 2000).--Some of this material is outdated because wild coastal coho are now federally listed as Threatened and wild coastal steelhead are a candidate for federal listing. There is more concern about wild salmonids, and, consequently, fisheries have been curtailed. Starting in 1996, the Oregon Legislature passed bills to permit cormorant hazing in Tillamook County, with annual funding of $25,000; hazing has subsequently occurred in Nehalem, Tillamook, and Nestucca estuaries.

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An updated analysis of cormorant hazing is in Studies in Oregon Ornithology No. 9.

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