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Bird Control Program Forward Landfill—Manteca, California _ Gull use of the North County Landfill has increased over the three year study period. During the November through March period, the average numbers of gulls per survey have increased from 709 in 2010-11, to 1,574 in 2011-12, to 2,462 in 2012-13. The migration of the last gulls out of the area occurred later in the spring of 2012 (early May)than in 2011 or 2013 (early April). The Foothill Landfill is located approximately 20.5 miles ENE of the Forward Landfill. It was surveyed 26 times from 3 September 2012 to 22 April 2013. Numbers of gulls were small (15 _ per survey) on 4 surveys in September. Numbers remained small in October with an average of 1.5 birds per survey on two surveys with only 3 present on 29 October. Numbers increased markedly in November with an average of 3,100 gulls (n = 2 surveys, peak 3,800 on 14 November). Numbers in December at Foothill Landfill averaged 1,800 (n= 2, peak 2,400 on 3`d) _ In January 2013, the average was 3,533 per survey (n = 3, peak 6,200 on 17th). In February, there were 2,350 gulls per survey(n=4,peak 3,200 on 25th). The overall numbers of gulls at Foothill Landfill was higher in 2011-2012 than in 2010-2011. There were 11 usable surveys conducted at Foothill Landfill in the November-March period of 2010- 2011 (Davis 2011). On those surveys there was an average of 1,077 gulls present per survey with a peak of 3,120 on 22 March 2011. During the November 2011 through March 2012 period (Davis 2012), there were 17 surveys conducted with an average number of gulls per survey of 2,087 per _ survey. In the present study,there was an average of 2,450 gulls on 14 surveys during the November 2012 to March 2013 period(Table 4). Thus,the average numbers of gulls at the Foothill Landfill has increased over the three year period. The results from North County and Foothill landfills clearly indicate that significant numbers of gulls use these landfills even though there were sporadic control efforts at each of the landfills. In both cases, there were significantly more gulls present than there were in the vicinity of the Forward Landfill during the same period. In addition, the gulls at North County and Foothill Landfills were feeding whereas those at Forward Landfill were scared away before they could feed. Therefore, the — numerical data are not directly comparable. Furthermore, the numbers for North County and Foothill landfills are the averages of the peak numbers per survey. The closest comparisons from Forward Landfill are the averages of the peak numbers in Appendix 1. For example, over the five month period (November-March.), the average peak number of gulls in the vicinity of the Forward Landfill was 45 gulls compared to the 2,450 at Foothill Landfill and 2,461 at North County that were actually feeding at those landfills. Also,the gulls at Forward Landfill scared away quickly or were flying past the landfill whereas the gulls at the other two landfills were present there for most of the day. Where Did the Gulls from Forward Landfill Go? The question was asked where did the gulls that formerly fed at Forward Landfill go when they were prevented from feeding at that landfill. A detailed assessment of this question — has not been conducted because it would have required intensive effort to collect baseline data in previous years before the control program began. Clearly, many of the gulls from Forward now go to other landfills in the region and feed at other areas. All of the natural feeding areas on waterbodies and in fields are still used by gulls. In addition, other anthropogenic or human created feeding sites are used. For example, gulls are using the Waste Transfer Station in south Stockton, the Town of Manteca, and the Stockton Sanitation Ponds. — Mi 9 30 December 2013