Feral swine damage and damage management in forested ecosystems

Invasive feral swine (Sus scrofa) cause deleterious impacts to ecosystem processes and functioning throughout their worldwide distribution, including forested ecosystems in the United States. Unfortunately, many feral swine damage management programs are conducted in a piecemeal fashion, are not adequately funded, and lack clearly stated or realistic objectives. This review paper identifies damage caused by feral swine to forest resources and presents techniques used to prevent and control feral swine damage. Concluding points related to planning a feral swine damage management program are: (1) the value of using a variety of techniques in an integrated fashion cannot be overstated; (2) there is value in using indices for both feral swine populations and their damage pre and post management activities; (3) innovative technologies will increasing be of value in the pursuit of feral swine damage reduction; and (4) though not appropriate in every situation, there is value in involving the public in feral swine damage management decisions and activities.

AN OVERVIEW OF DEPREDATING BIRD DAMAGE CONTROL IN CALIFORNIA

To many people, California is synonomous with Disneyland, freeways, Los Angeles smog, Yosemite, the California missions, or for you bird aficionados, the California Condor. But do you think about California when you eat strawberry shortcake? You should -- California leads the nation in strawberry production. How about artichokes? California produces over 98% of the artichokes raised in the United States. Dates? California produces over 99% of the dates in the United States. Yes, California is all of these, and it is much more. California may well be the most diverse state in the United States. Within its 100.2 million acres, California has the lowest place in the U.S. in Death Valley and one of the highest mountains with Mt. Whitney. Because California is such a diverse state and has a wide variety of micro- climates, it supports a uniquely diverse agriculture. Agriculture uses only about 36 million acres of its total 100.2 million acres, and most of the cash return from crops is produced on 8,6 million acres that are irrigated. California produces about 250 crops and livestock commodities (excluding nursery crops) and provides the U.S. with about 25% of its table foods. California leads the nation in the production of 46 commercial crops and livestock commodities; its farmers and ranchers marketed $8.6 billion of crop and livestock products in 1975, and the state’s harvested farm production in 1975 set a new record at 51.1 million tons. HISTORY OF BIRD PROBLEMS Records such as this are not achieved without some risk. Crops growing in Cali- fornia have always had competition from many types of vertebrate pests. The wide variety of crops grown in California and the varied climates and situations in which they are grown has resulted in many different species of birds damaging crops. Birds have compet- ed with man for his crops since the dawn of agriculture. McAtee (1932) cited examples of bird damage that occurred in a wide variety of crops in California during the early 1900s. During the 1920s, many requests for Information and relief from damage caused by a wide variety of birds, culminated in the assignment, in May 1929, of two biologists, S. E. Piper and Johnson Neff, of the former U.S. Bio- logical Survey, to initiate field studies in California. In cooperation with the Cali- fornia Department of Food and Agriculture and County Agricultural Commissioners, the study was to determine the problems and devise control procedures relative to bird depredations. Piper and Neff found such damage as Horned Larks pulling sprouting crops, House Finches disbudding deciduous fruit trees and devouring mature fruit. Blackbirds were a problem in the rice crop. Early controls were varied and, for the most part, lacked effectiveness. Flagging of fields was common to deter Horned Larks. Windmill devices were tried to frighten birds. Shooting to kill birds was common; scarecrows were.used. The six-year study brought forth the basis of most of the depredating bird control techniques still in use in California. At the end of the study, these two biologists compiled a book called “Procedure and Methods in Controlling Birds Injurious to Crops in California.” This was and still is the “Bible” for bird damage control techniques used in California. The thorough investigations conducted by these biologists resulted in techniques that have remained valid in California for over 40 years.

A history of wildlife damage management: twelve lessons for today

The history of wildlife damage management in the United States, beginning with the roots of the federal Biological Survey, is examined. Selected lessons are drawn from history and applied to today's situation, in the hope that they will be useful to those who guide this profession in the 21st Century.

1969 ASSESSMENT OF BLACKBIRD DEPREDATIONS ON FIELD CORN IN OHIO AND MICHIGAN

In 1966, when the annual damage survey was initiated, Dr. C. R. Weaver, Statistician at the Ohio Agriculture Research and Development Center, Wooster, Ohio, drew up a sampling plan, balancing costs against desired precision. The plan included three combinations of fields to be sampled and stations per field for high damage areas, three combinations for moderate damage areas, and two combinations for light damage areas. Alternatives for the high damage area included (1) 497 fields with two stations per field (± .48), (2) 775 fields with two stations per field (± .26), and (3) 235 fields with ten stations per field (— .68). For the moderate damage areas, the alternatives were (1) 441 fields with three stations per field (± .26), (2) 155 fields with three stations per field (± .50), and (3) 235 fields with ten stations per field (± .32). The light dam¬age area alternatives were (1) 297 fields with three stations per field (- .26), and (2) 81 fields with three stations per field (± .50). The original survey in 1966 sampled eight counties in three regions. In 1967, 14 counties in the same three regions were sampled. Two new counties were added to one region and two new regions with two counties each (treated as one region for sampling purposes) were added to the 1968 survey. The 1968 survey was of sufficient size to be representative of the corn damage picture in Ohio and Southeast Michigan. The 1969 survey was identical to the 1968 survey.

ENHANCEMENT OF THE FAA’s ON-LINE WILDLIFE AIRCRAFT STRIKE DATABASE WITH AN INTERACTIVE GRAPHICS CAPABILITY

Embry-Riddle Aeronautical University (Prescott, AZ, USA) was awarded a grant from the William J. Hughes FAA Technical Center in October 1999 to develop and maintain a web site dealing with a wide variety of airport safety wildlife concerns. Initially, the web site enabled users to access related topics such as wildlife management (at/near airports), bird identification information, FAA wildlife management guidelines, education, pictures, current news, upcoming meetings and training, available jobs and discussion/forum sections. In April 2001, the web site was augmented with an on-line wildlife strike report (FAA Form 5200-7). Upon submittal on-line, “quick look” email notifications are sent to concerned government personnel. The distribution of these emails varies as to whether there was damage, human injuries/fatalities, and whether feather remains were collected and will be sent to the Smithsonian Institution for identification. In July 2002, a real-time on-line query system was incorporated to allow federal and local government agencies, airport and operator personnel, and USDA and airport wildlife biologists to access this database (which as of June 2005 contains 68,288 researched strike reports added to at a rate of approximately 500 strike reports/month) to formulate strategies to reduce the hazards wildlife present to aviation. To date (June 2005), over 15,000 on-line real-time queries were processed. In June 2004, ERAU was authorized to develop a graphical interface to this on-line query system. Current capabilities include mapping strikes (by species) on the US map, each of the contiguous 48 state maps (with AK and HI being added), and airport diagrams of the major metropolitan airports as well as the next 46 airports with the most reported strikes The latter capability depicts strikes by runway in plan as well as in elevation view. Currently under development is the ability to view time-sequenced strikes on the US map. This extensive graphical interface will give analysts the ability to view strike patterns with a wide variety of variables including species, seasons, migration patterns, etc. on US and state maps and airport diagrams.