Nearshore Habitat Use by Juvenile Chinook Salmon in Lentic ...

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Observations were conducted primarily in the morning when the water was calm and fish could be easily observed. On windy days, no observations could be conducted. Observations were made by standing on the pier and observing schools of Chinook salmon as they swam near the pier (Figure 49). The time each school was observed and the direction they are swimming was noted. The size of each school of Chinook salmon was categorized as either small (< 50 fish), medium (50-100 fish), large (100-200 fish) or very large (> 200 fish). How Chinook salmon responded to the pier was determined by estimating the depth of each school as the approached the pier and the depth they were at as they past under or around the pier. Results Surface observations at the McClellan Pier were conducted once a week from May 21 to July 3 in 2003 and May 19 to July 9 in 2004. During the first five surveys in 2003 (May 21 to June 18), few juvenile salmonids were observed and no obvious movements were seen. Similarly in 2004, few Chinook salmon were observed until June 16. On June 26, 2003 and June 16, 2004, large numbers of salmonids were observed moving along the shoreline. Based on fish size and date, we assumed they were juvenile Chinook salmon. Snorkel surveys conducted in 2004 also indicated they were Chinook salmon. To better understand fish movements, we conducted additional surface surveys during the period when Chinook salmon were abundant. The timing of the migration appeared to coincide with the moon apogee, which has been also suggested to be related to the passage of Chinook salmon smolts at the Ballard Locks (DeVries et al. 2004). When Chinook salmon were abundant at McClellan Pier, we took extended observations to collect additional information on migrating Chinook salmon. In 2003, extended observations were conducted twice (June 26 and July 1) and in 2004 they were conducted three times (June 16 to 18). On all five dates, observations were conducted from at least 0730 h to 1100 h (Figure 50). Peak number of schools was observed between 0800 h and 0830 h and the lowest abundance was at the end of the survey between 1030 h and 1100 h. However, results of an ANOVA test indicated there was no significant difference in abundance for any half hour period between 0730 h and 1100 h. Additional observations were conducted if weather conditions and personnel schedules permitted. On one date, June 16, 2004, we were able to make observations from 0600 h to 1200 h (Figure 51). On this date, few schools of Chinook salmon were observed before 0730 h and after 1100 h. Observations on other dates showed the same general trend; little activity before 0700 h and a reduction in activity after 1100 h or 1200 h. 83
FIGURE 49.—Conducting visual observations of migrating Chinook salmon at the McClellan Street pier, Lake Washington. 25 20 Percent 15 10 5 0 7:30 8:00 8:30 9:00 9:30 10:00 10:30 Time FIGURE 50.—Percent of Chinook salmon schools occurring in half hour intervals between 0730 h and 1100 h, McClellan Pier, Lake Washington. Bars represent the mean percent of five dates, June 26, 2003, July 1, 2003 and June 16 to 18, 2003. 84
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U.S. Fish and IU.S. Wildlife FishSe
Page 3 and 4:
SUMMARY In 2003 and 2004, we contin
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An overhanging vegetation/small woo
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Table of Contents Page SUMMARY ....
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List of Figures Figure Page FIGURE
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FIGURE 37.—Water column depth (m)
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The major tributary to Lake Washing
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Fry emerge from their redds from Ja
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FIGURE 2.—Location of index sites
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most dates (Figure 4). Unlike 2002,
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Chinook/m 2 1 0.8 0.6 0.4 0.2 0 Wes
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0.3 Mercer Island Chinook/m 2 0.2 0
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particularly valuable. Shoreline im
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FIGURE 8.—Map of south Lake Washi
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FIGURE 10—Map of south Lake Washi
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# of marked Chinook 40 30 20 10 0 A
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CHAPTER 3. RESTORATION SITES Introd
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Beer Sheva Park.—At Beer Sheva Pa
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Results Seward Park, 2003.—In 200
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4 3.5 Chinook/100 m 3 2.5 2 1.5 1 0
Page 41 and 42:
Martha Washington Park, 2003.—In
Page 43 and 44: 120 Chinook/100 m 100 80 60 40 20 s
Page 45 and 46: snorkeling and scuba diving were co
Page 47 and 48: Water column depth (m) . 0.80 0.60
Page 49 and 50: CHAPTER 5. FEEDING AT TRIBUTARY MOU
Page 51 and 52: FIGURE 28.—Location of four south
Page 53 and 54: FIGURE 29.—Photos of sites used t
Page 55 and 56: sampling. At night, Chinook salmon
Page 57 and 58: TABLE 5.—Diet overlap indices (C)
Page 59 and 60: TABLE 7.—Diet overlap indices (C)
Page 61 and 62: TABLE 10.—Diet composition of juv
Page 63 and 64: The lack of a large difference betw
Page 65 and 66: CHAPTER 6. USE OF NONNATAL TRIBUTAR
Page 67 and 68: shallow to snorkel were surveyed th
Page 69 and 70: Number of Chinook ff 700 600 500 40
Page 71 and 72: column depth used by Chinook salmon
Page 73 and 74: Chinook / m . 5 4 3 2 1 2003 - upst
Page 75 and 76: TABLE 13.—Diet overlap index (C)
Page 77 and 78: (P. Castle, WDFW, unpublished data)
Page 79 and 80: FIGURE 41.—Placement of Scotch br
Page 81 and 82: FIGURE 43.—Photo of a group of ju
Page 83 and 84: CHAPTER 8. LAKE QUINAULT SURVEYS In
Page 85 and 86: FIGURE 45.—Photos of large woody
Page 87 and 88: Similar to April surveys, the nears
Page 89 and 90: Chinook / 100m . 500 400 300 200 10
Page 91 and 92: Tabor and Wurtsbaugh (1991) conclud
Page 93: FIGURE 48.—Location of south Lake
Page 97 and 98: FIGURE 52.—Photo of a group of ju
Page 99 and 100: ACKNOWLEDGMENTS We wish to thank He
Page 101 and 102: workshop, Shoreline, Washington, No
Page 103 and 104: Paron, D.G., and E. Nelson. 2001. S
Page 105 and 106: Werner, E.E., and D.J. Hall. 1988.
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Nearshore Habitat Use by Juvenile Chinook Salmon in Lentic ...

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