In all cases, film exposure intervals were set less than 

 the time a person could move across the camera's field of 

 view. A fast walker or a horse might go about 5 feet per 

 second. If the field of view was 50 feet, this would require 

 about 10 seconds. An exposure interval of 6 or 7 seconds 

 provides some margin of error, and enough overlap to 

 positively record the party composition. We used 

 intervals from 4 to 10 seconds at the various locations 

 where the permit station was in the camera's view. 



Where the camera was focused on the permit station, 

 120 to 180 seconds from beginning to ending filming indi- 

 cated clearly if the party complied, even if they had not 

 always finished writing and depositing the permit when the 

 camera shut off. 



The movie camera used color, super-8 film cassettes 

 that provided about 3,500 frames. Usually, each party 

 triggered the camera twice (in and out). A party with 

 several members retriggered the camera and exposed 

 more film. (The camera initiated a new cycle for each 

 triggering impulse). Thus, film consumption is somewhat 

 greater than twice the number of frames selected for 

 exposure per party, times the number of parties. 



Heavily used Spanish Creek and Cascade Creek were 

 visited for servicing at least twice a week and all other 

 sampling locations at least once a week. If there was any 

 chance that the film could be exhausted before the next 

 visit, it was removed, labeled, and sent in for developing. 

 When new film was installed, a few frames were exposed 

 to photograph a card marked with the location and date. 



Triggering the camera when persons passed was far 

 superior to simple time lapse photography. With 10-second 

 exposure intervals, film would be exhausted in about 10 

 hours and very few exposures would include visitors. 



Film was viewed as soon as possible to identify any 

 field equipment problems that might need to be corrected. 



Protection of Privacy 



Both the letter and spirit of privacy laws were fully 

 observed. Forest Service legal counsel has advised that 

 automatic cameras are legal for use as traffic measuring 

 and classifying devices. 



Cameras were located and focused so individuals 

 could not be identified. (The pilot test in 1977 showed that 

 individuals were indistinguishable. The two persons who 

 installed the camera and then walked the trail could only 

 distinguish themselves by clothing colors.) Film was kept 

 secured by the field technician and was viewed only by her 

 or authorized officials. After all data were recorded, the 

 film was kept locked securely for 3 months for possible 

 rechecking, and then it was all destroyed. Film was 

 intended to be used only to record use, and this was what 

 the public was told. Therefore, it was decided that it would 

 not have been available for use as evidence in any proceed- 

 ings against violators, if such a situation developed. (It 

 did not.) 



A press release to inform the public of the use of 

 cameras was issued by Gallatin National Forest officers. 

 The press release stated that cameras would be used to 

 measure use, but did not indicate that they were focused on 

 the permit stations. This, together with limited readership 

 of the press release, should have avoided influencing 

 visitors' permit issuance behavior. 



Traffic Classification, Permit 

 Compliance 



A form was used to record observations from film 

 (appendix 2). Method of travel (horseback riders, hikers, 

 and hikers with packstock) was easily observed. Day-users 

 and campers were classified primarily by noting whether 

 people had large backpacks or packhorses. Day-users 

 were classified by approximate length of stay, using the 

 hourly marked exposures. Group size was classified as 

 well as possible, but, in a few cases, parties were strung 

 out and it was not possible to determine positively who was 

 with whom. We attempted to identify hunters by rifles, but 

 photo quality made this impossible in many cases. 



If persons remained at the permit station, apparently 

 filling out forms, and they were still doing so when the 

 camera shut off, it was assumed that they had complied. 



Permit Tabulation 



Permits were collected whenever the field assistant 

 visited a trailhead. The trailhead name was marked on all 

 of the completed permits. Permits were kept in sequence 

 to aid in estimating dates for any that lacked date of entry. 



Permits were compared to the projected film to confirm 

 compliance or noncompliance. For Spanish Creek, this 

 was necessary to make the compliance classifications. 

 At other locations, if parties entered in darkness (especially 

 common in the fall), it was sometimes possible to recon- 

 struct events with the use of permits if such parties exited 

 during daylight hours, so they could be classified in terms 

 of method of travel, party size, and so forth. 



Permit Station Location 



All permit stations were classified as "end-of-road" 

 or "up-the-trail" (if out of sight of the parking area) for 

 analysis of the effect of location. 



ANALYSIS PROCEDURES 

 Variables Analyzed 



Results are primarily descriptive and comparative. 

 Tabulations were made for permit compliance related to 

 the following single variables believed to influence visitor 

 responses: 



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