FORESTRY

HANDBOOK

Second Edition

Edited for the Society of American Foresters

by

KARL F. WENGER

A W1LEY-INTERSC1ENCE PUBLICATION

JOHN WILEY & SONS

NEW YORK • CHICHESTER • BRISBANE • TORONTO • SINGAPORE

* f

Copyright © 1984 by John Wiley & Sons, Inc.

All rights reserved. Published simultaneously in Canada.

Reproduction or translation of any part of this workbeyond that permitted by Section 107 or 108 of the1976 United States Copyright Act without the permissionof the copyright owner is unlawful. Requests forpermission or further information should be addressed tothe Permissions Department, John Wiley & Sons, Inc.

Library of Congress Cataloging in Publication Data:Main entry under title:Forestry handbook.

"A Wiley-Interscience publication."Includes bibliographies and index.1. Forests and forestry—Handbooks, manuals, etc.

I. Wenger, Karl F., 1918- II. Society of AmericanForesters.SD373.F58 1983 634.9 83-17110ISBN 0-471-06227-8

SAP Publication Number SAF 84-01

Printed in the United States of America

1 0 9 8 7 6 5 4 3 2 1

K A R L F. WBurgess,

WILLIAM RDepartmi

ConserUniversitStorrs, C

F. BRYAN CForest ScWashing!

DUANE E. IWisconsi

ResourMadison,

JOHN R. HiForest SeWashing!

DAVID E. ¥Forest S«Washingi

X SECTION AUTHORS

ReviewersJOHN J. GARLAND, Extension Service, Oregon State University, Corvallis, OregonW. B. STUART, School of Forestry and Wildlife Resources, Virginia Polytechnic Insti-

tute and State University, Blacksburg, Virginia

SECTION ON FOREST PRODUCTS UTILIZATION

A ulhorsHERBERT C. FLEISCHER, Senior Author. (Director, FPL, Retired) Middleton,

WisconsinERWIN, H. BULGRIN, Forest Products Laboratory, Forest Service, USDA, Madison,

WisconsinJEANNE P. DANIELSON, Forest Products Laboratory, Forest Service, USDA, Madison,

WisconsinDONALD F. FAHEY, Forest Products Laboratory, Forest Service, USDA, Madison,

WisconsinROBERT C. KOEPPEN, Forest Products Laboratory, Forest Service, USDA, Madison,

WisconsinJOHN H. McGovERN, Forest Products Laboratory, Forest Service, USDA, Madison,

WisconsinJOHN I. ZERBE, Forest Products Laboratory, Forest Service, USDA, Madison,

Wisconsin

ReviewersARTHUR F. MUSCHLER, Edward Hines Lumber Co., Chicago, IllinoisSTEPHEN, B. PRESTON, School of Natural Resources, University of Michigan, Ann

Arbor, Michigan

SECTION ON FOREST HYDROLOGY AND WATERSHED MANAGEMENT

A uthorsJAMES W. HORNBECK, Senior Author. Forest Service, USDA, Durham, New

HampshireEDWARD S. CORBETT, Forest Service, USDA, University Park, PennsylvaniaPAUL D. DUFFY, Forest Service, USDA, Oxford, MississippiJAMES E. LYNCH, School of Forest Resources, Pennsylvania State University, Univer-

sity Park, Pennsylvania

ReviewersEDWIN L. MILLER, Weyerhaeuser Co., Hot Spring, ArkansasJAMES NELSON, Bureau of Forestry, Harrisburg, Pennsylvania

SECTION ON FOREST WILDLIFE AND FISH MANAGEMENTA uthors

LOWELL K. HALLS, Senior Author. Forest Service, USDA, Nacogoches, TexasDAVID S. DECALESTA, Department of Fisheries and Wildlife, Oregon State University,

Corvallis, OregonROBERT L. DOWNING, Fish and Wildlife Service, USDI, Clemson, South CarolinaFRED H. EVEREST, Forest Service, USDA, Corvallis, OregonRICHARD F. HARLOW, Forest Service, USDA, Clemson, South CarolinaTHOMAS J. H A R S H B A R G E R , Forest Service, USDA, Asheville, North CarolinaJAMES C. KROLL, School of Forestry, Stephen F. Austin State University, Nacog-

doches, TexasJAMES S. LINDZEY, Fish and Wildlife Service, USDI, Centre Hall, Pennsylvania

JOHN H. MEV I R G I L E. S'

ReviewersJAMES J E N K IDAVID R. P

SECTION ON

A uthorsGRANT A. lh

WashingtiGLENN R. PROBERT F. :JOHN DRAKROBERT W.HENRY A . IJOHN L. ScLAMAR SMI

Tucson, /

ReviewersVERGIL L. 1GERHART HROBERT M.

SECTION ONA uthors

ROBERT C.WARREN, RWENDELL BPERRY J. BHARRIET HROGER N. (DAVID N. CB. L. DRIVIWILLIAM CHUNTER H<DAVID A. \

son, ArizWILBUR, F.JOEL E. MEGEORGE W.

MinnesoiJACK SCHUGEORGE H.PAUL D. W

ReviewersKENT B. DiDARRELL E

SECTION OfvA uthors

H. KEN Co

706 FOREST WILDLIFE AND FISH M A N A G E M E N T FISH

E. Control measures that remove a proportion less than the maximum rate of in-crease will reduce but not eliminate the population.

FISH CENSUS. To conduct an analysis of a fish population, the manager should de-cide exactly what kind of information he needs and then use the simplest method to obtainit. Censusing is usually conducted in streams and / or lakes by one of the following methods:(1) passive and actively fished nets, (2) traps and weirs, (3) treatment with toxicants, and(4) electrofishing.

Stream Sampling. Stream size and local conditions often indicate the best samplingtechnique to use. In large streams, nets can be placed to obtain a cross section of a popula-tion at a certain depth. Set nets commonly employed include fyke, hoop, trap, and gill nets.Such nets, in general, depend on active movement of the fish. Movement may be stimulatedwith copper sulfate, light, electrical fields, and noise. Sets should be made down wind ordown current, with the net well stretched and securely anchored. Floating debris and thebias produced by mesh size and fish availability during daylight hours should be considered.All nets are selective for a particular size and/or species offish. To reduce selectivity, fleetsor gangs of nets of various size are often used. Replicate sets provide information that canbe statistically tested.

Actively fished nets include seines, trawls, and drift gill nets. Seines are often used insmall streams or shallow portions of a large stream by fishing them parallel to the streambank or from across stream to the bank. Seines must be leaded for the bottom conditionsthey will be hauled over. Loosely hung nets that produce a good bag when hauled are moreeffective than tightly hung ones. Large fish usually avoid seining. Trawls and drift gill netsare occasionally used in large, deep, slow-moving streams or rivers. Traps and weirs are ex-pensive to construct and difficult to maintain, but are often used to obtain population esti-mates for runs of fish which are economically important.

Properly used, toxicants can give a complete population distribution in a stream section.The most commonly used toxicants are rotenone, toxaphene, Fintrol (Antemycin) cresol,and sodium cyanide. To prevent fish avoidance, toxicants must mix completely with thewater column being sampled. Unexpected side effects can be a problem when toxicants aieused. Government licensing or approval must be obtained for any compound that is used inwater or on fish that are consumed by man or animals. Some compounds affect other or-ganisms as well as fish. The rapid downstream spread of a toxicant in a stream or river mustbe controlled and this requires experience with the particular compound employed. Detoxi-fication and dilution are methods commonly used to control the spread of a toxicant.

Electrofishing is probably the most used technique for sampling fish in small streams.The efficiency of electrofishing gear is governed by water conductivity and the experienceof the operators. Fish species also differ in their susceptibility to electrical fields and largefish are more easily captured than smaller fish because they present a larger surface area.Generally, ac current works better in soft-water streams (conductivity less than 200 mi-cromhos). dc current can be used effectively where conductivity exceeds 200 micromhos.Boat-mounted units are usually employed in larger streams and rivers where wading is notpractical, and backpack electrofishing units are used in smaller watercourses. Both types ofequipment are available from commercial sources.

To take a census of a stream, several sections of known length should be electrofished.Sections should contain typical stream conditions and be long enough to obtain a represen-tative sample of the fish population. Block nets are natural barriers to fish movement andshould be employed to prevent migration in or out of the section while it is being sampled.Operators of electrofishing gear should be thoroughly familiar with their equipment andthe potential hazards associated with electricity and water. Waders and rubber lineman'sgloves must be worn at all times by those using the electrodes and scrape nets. In use, theelectrodes are placed in the water and moved ahead of the operator who slowly traverses thestream in an upstream direction. Stunned fish are dipped from the water with scape nets and

placed in a holdpopulation esti1

Explosive d(cants and elect:

Lake Samplcan be obtainccthe fish with a Iobtain statistic;

Net samplesas gill and t rapmetric pressurelight can affect

Seines and sface debris. Seisample of the ]

Electrofishilake shockingunderwater lig

Pelagic fishselectively certsoft or rough ;

Each metricmore ways she

General Saunit fishing ef;live abundanchaul, a fixed 1standard gear

Direct enutual count. T.move througVdrained and tremains,the s;and results pi

In some fion the numbsof adult salrrspawning adi

Mark-re«port a recreaare the singlemethod, fishis made thaimethod, marcorded by tirincreases, th'are marked,distinctly difrecorded, aslation canno

The basicmore mortal

r--mK,

n rate of in-

• should de-)d to obtainig methods:.icants, and

st sampl ing>f a popula-nd g i l l nets,s t imula ted

Nn wind orris and the:onsidered.ivity, fleets3n that can

ten used inthe streamcondi t ionsd are moreift g i l l netseirs are ex-lation esti-

im section.:in) cresol.y w i t h thedcants a r et is used int other or-river mustd. Detoxi-x ican t .I I s treams,jxperienceand larL-e

•face area.n 200 rr.:-icromhos.ling is noth types o!

tro fishes.!.represc:;-ment u r - isample :.

ment a; .Jl i n e m a : "*n use. tWverses t::--'; neisar .J

FISH WILDLIFE POPULATION ANALYSES AND CENSUS TECHNIQUES

placed in a holding box. Repeated electrofishing between stopnets or barriers can yield goodpopulation estimats without harming the fish.

Explosive detonator cord is used occasionally in remote streams where access with toxi-cants and electrofishing equipment is difficult.

Lake Sampling. A rough estimate of the species composition and abundance of fishcan be obtained by sectioning off a portion of a lake with block seines and eradicating allthe fish with a toxicant such as rotenone. A large number of samples is usually required toobtain statistically reliable results.

Net samples can be used to obtain a cross section of the fish population. Fixed nets, suchas gill and trap nets are selective in that they depend on fish movement. Changes in baro-metric pressure, wind-driven currents, water level fluctuation, turbidity, and transmittedlight can affect efficiency and selectivity of passive nets.

Seines and seining can be used in small lakes and ponds which are free of bottom and sur-face debris. Seine hauls should be made from different locations to obtain a representativesample of the population.

Electrofishing can be used effectively if the water is not too deep or turbid. Efficiency oflake shocking is enhanced if conducted during hours of darkness, supplemented with anunderwater light.

Pelagic fish are often sampled with a trawl. Towing depth can often be used to sampleselectively certain species and year classes of fish species. Bottom trawls are often effective onsoft or rough substrates and in shallow water.

Each method can be selective for a certain species and size of fish. Thus, at least two ormore ways should be employed when sampling a large population.

General Sampling Techniques. The catch from a standard gear unit or the catch perunit fishing effort can be used as an index where the manager needs only to know the rela-tive abundance of a fish stock. Electrofishing over a standard course, a standardized seinehaul, a fixed length and mesh-size gill net, and a rotenone sample of a cove are consideredstandard gear units.

Direct enumerations are preferred when the population can be confined to make an ac-tual count. T Jtal counts are often conducted in conjunction with spawning runs where fishmove through fishways, weirs, traps, or selected stream reaches. Small ponds can often bedrained and the population enumerated by seining. Where the fish population abundanceremains the same and is uniform throughout the water body, stratified units can be sampledand results projected to the entire population.

In some fish populations, the number of adults may be related to egg or fry productionon the number of nests or redds. For example, fry indices have been used to forecast returnsof adult salmon. The nests of certain fishes may also be used to estimate the number ofspawning adults.

Mark-recapture methods are adapted for use on small, discrete stocks of fish that sup-port a recreational fishery and for which catch statistics are difficult to obtain. Estimatesare the single census, multiple census, and multiple recapture method. In the single censusmethod, fish are captured, marked, and released, and then, at a subsequent time, a total catchis made that contains both marked and unmarked individuals. In the mult iple censusmethod, marked fish are repeatedly added to the population while the removed fish are re-corded by time period to yield an estimate of population size. As the number of marked fishincreases, the variance of the estimate decreases. For the multiple recapture method, fishare marked, subsequent recaptures are noted and returned, and unmarked fish are given adis t inc t ly different mark; fish are again captured, and the previous marks of both categoriesrecorded, as well as unmarked individuals. This method should be used when a closed popu-lation cannot be assumed.

The basic assumptions underlying mark-recapture methods are: (1) marked fish have nom»re mortality than unmarked; (2) marked fish are caught at the same rate as unmarked;

-'•Hi-

708 FOREST WILDLIFE AND FISH MANAGEMENT

(3) marks are not lost; (4) marked fish are randomly distributed or the sampling effort israndom; and (5) recruitment is negligible or can be estimated.

Creel data (a creel census) is an expression of catch per unit fishing effort, and is oftenused for year-to-year comparisons. The data can sometimes be used to estimate populationsby taking the composition of the catch into consideration. For example, the relativeabundance of two or more kinds off ish in the population is first determined, changes in therelative abundances are made by removing (fishing) known numbers and kinds of individ-uals, and then estimates of the new relative abundances are made.

Where extensive creel census data exists, the virtual population can be used to estimatethe actual population. The virtual population is the minimum estimate of catchable fishpresent in 1 year, or a total of the minimum number offish in existence of each year class.To estimate the actual from the virtual population, a number of fish must be permanentlymarked and the number of recaptures recorded in following years.

The number of fish can also be found by sampling the population several times and plot-ting a regression line of catch per unit effort on the cumulative catch for each time period.This method is often used in stream censusing where block seines, holding boxes, and elec-trofishing gear are employed.

Capturing, Marking, and Monitoring Wildlife

CAPTURE. Frequently the wildlife manager captures animals to reduce the popula-tion density, restock, control damage, and conduct research. Capture of wild animals isexpensive and time-consuming; consequently, it should be undertaken only when absolutelynecessary. Furthermore, live capture is usually regulated by both state and federal agencies.Trapping should be coordinated with appropriate groups, especially when threatened or en-dangered species are involved. The most commonly used capture techniques are presentedin Table 7.

Planning of live captures should include consultation with individuals experienced incapture of the species being studied. Capture techniques successful in any one particularsituation may be unsuccessful in another. For example, white-tailed deer are easily capturedat high population densities using box traps, while at lower population levels, more inno-vative (and expensive) techniques such as tranquilizer darts, helicopters, or drop nets maybe necessary. Two or three feasible techniques should be employed to assure success.

MARKING. Marking devices range from inconspicuous bands to prominent, bright-colored tags. In choosing a marking device, one must consider the nature of the study andthe possible effect of marking on the animal's behavior and survival. An ideal marker shouldeasily identify a specific individual without restricting movements, influencing intraspecificbehavior, or increasing mortality. Conspicuous tags render some species more susceptiblethan others to predators. For example, wing tags on pheasants can increase predation byraptors.

MONITORING. Monitoring systems for wild animals should only be utilized whenabsolutely necessary. If improperly employed, such techniques add little to basic knowledgeabout a species.

Radio-telemetry has been extensively used in monitoring studies during the last 20 years.It is extremely useful in that, under proper conditions, behavior is little affected by the ob-server or equipment. Simple systems consisting of radio-tags, receiver, and antennas costSI000-2000, whereas elaborate tracking stations utilizing continuously monitoring com-puter systems may exceed SI,000,000. Reliable radiotelemetry systems, no matter the levelof sophistication, should include: (!) tracking systems of known accuracy, (2)precise basemaps of the management area on which to plot locations, and (3) some system for manipu-lating large amounts of data. Bearings, azimuths, and locations ("fixes") should not betaken on faith. Errors in readings are caused by observer, antenna and receiver type, topog-

raphy, and weathto in i t i a t i on of n:not related to catscntial to radiotr ,data: thus, a dataSuch systems a l l <

Movement ofby aircraft. This iMarked individu;server or vehiclements are also diuse of the "betapermit is needed

Natural souncTracking stationsdirectional microtechniques.

Vegetation measiing reasons: to fiwhat kind of plaiit is getting betteienvironment. Theof wildlife, such ;tial to support theof timber managican determine thmaintain or implargely by the puiSubjective sampl:Objective measurbut usually theyattributes is so laacceptable in exfor research activicosts and expects

The vegetatioi(botanical comptoccurrence), densmaps and deline;t imber type, drairately for each s;summation and c

BOTANICALmake a reconnaisqualitative assess«n the number,comparisons.

Plant speciesproduce food, coheight, and/or cr