MLPA NCSR Baseline Seabird Nearshore Foraging and Feeding Flock Monitoring Protocol Point Blue Conservation Science

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1 MLPA NCSR Baseline Seabird Nearshore Foraging and Feeding Flock Monitoring Protocol Point Blue Conservation Science OVERVIEW This document provides instructions for collecting data within the North Coast Study Region of California s Marine Life Protection Act (MLPA) for the following two parameters: Nearshore Foraging and Feeding Flocks. Both parameters are included in this one document because they are measured during the same survey. In this document, nearshore foraging is defined as foraging by individual animals in shallow subtidal habitats within 1 km of shore. Feeding flocks are considered large aggregations of animals (>5 individuals) foraging on a single source of pelagic prey and can occur anywhere within the view of the observer. Nearshore foraging and feeding flocks typically occur at different scales of effort, with nearshore foraging involving 1s to 10s of individuals, and feeding flocks involving 10s to 1000s of individuals. OBJECTIVES Nearshore Foraging I. To document and compare seabird and marine mammal foraging inside and outside Marine Protected Areas (MPAs) II. To determine if seabird and marine mammal foraging activity changes III. throughout the day and/or throughout the breeding season. To determine the role that oceanographic conditions (i.e., wave height, wind speed, water surface quality, and tidal height) play in regulating seabird and marine mammal foraging activity. Feeding Flocks I. To document the location, frequency of occurrence, longevity, and the species composition of feeding flocks in nearshore waters. II. III. IV. To determine how feeding flock location, frequency, longevity, and species composition vary spatially (between study sites, or within study sites between areas with different substrates, oceanography, currents, or levels of exposure to oceanic conditions) and temporally (diurnally, with different stages of breeding, and interannually), and reasons for this variation. To determine how oceanographic variables (e.g., sea surface temperature, wind speed, wave height) influence the number, size, and distribution of foraging flocks within and among years. To assess differences in seabird feeding within and outside MPAs.

2 METHODS Nearshore Foraging. We have selected multiple sites at each study area to conduct foraging surveys, with some sites within an dmpa and other sites outside of the MPA boundaries. For each location, we have defined an area of 1km radius within which foraging observations will be made. Sites included: Del Norte County (dn; Figure 1) 1. Crescent City area (cc) a. Pyramid Point SMCA (ppc; ) b. Cresecnt City (ccx; ) Humboldt County (hu; Figure 2) 1. Trinidad Head area (th) a. Patrick s Point (ppt; ) b. Trinidad Bay (trb; ) 2. Cape Mendocino area (cm) a. South Cape Mendocino SMR (cmr; ) b. Devil s Gate (dga; ) Mendocino County (me; Figure 3) 1. Kibesillah area (ki) a. Kibesillah (kib; ) b. Ten Mile SMR (tmr; ) 2. Mendocino Headlands area (mh) a. Point Cabrillo SMR (pcr; ) b. Mendocino Headlands South (mhs; ) Observations on seabird foraging activity will be made once a week at each site. Observations will be conducted during the following three-hour time intervals: hrs., hrs., hrs., and hrs. Each site should be surveyed once during one of the time intervals each week, then surveyed again the following week in the next time interval. Use the following table as an example of how to rotate the time intervals. Week Pyramid Point Crescent City Patrick s Point Trinidad Bay

3 etc. etc. etc. etc. etc. Observations during each three-hour time interval will be divided into 15-minute blocks. At the beginning of each 15-minute block, record surface water conditions and visibility. Observations are collected within the boundary of a 1-km radius circle that is centered on the observer s position. Reference maps will be provided that divide the circle into 200m-radius increments. Distances may appear different depending on the observer s height above sea level; landmarks on the maps can be used to determine distances on land to estimate distance at sea. All seabird and marine mammal species observed foraging should be recorded. We are particularly interested in observations of the following species foraging within each defined study area: Brandt s cormorant, pelagic cormorant, double-crested cormorant, brown pelican, western gull, California gull, pigeon guillemot, surf scoter, western grebe, Pacific loon, California sea lion, harbor seal, and sea otter. For each 15- minute block, record the maximum number of individuals of each species observed foraging within the defined study area. Record only seabirds and marine mammals that are actively foraging (i.e., actively diving/feeding) and not those that are only rafting or are in transit through the study area. If an individual seabird or marine mammal is observed foraging within a feeding flock (see below for definition of a feeding flock), DO NOT include it in the nearshore foraging data. Nearshore foraging includes only animals foraging independently. Transfer data from field notebooks to computer after each survey in case the field notebook is lost. Figure XX is an example of how to record data in the data book. Feeding Flocks. A feeding flock is defined as five or more seabirds and/or marine mammals feeding on the same prey patch (usually a school of fish, squid, etc.). Record all flocks visible from each of the foraging observation points, regardless of distance from the observation point. Give a general, descriptive location of the flock (e.g., approximately 500m southwest of the Crescent City OP). Mention any distinguishable landmarks in the description and draw a map in the notebook if necessary. Record the start and end time of the flock if it occurs during the three-hour study period. If the flock was already underway when you arrived at the study area and/or has not ended by the time you are finished with your survey, you will not have start and/or end times. Record the number of individuals of each species observed participating in the flock every 15 minutes. Record all species observed, but the species of interest are the same as for Nearshore Foraging observations above. Record multiple feeding flocks individually (e.g. FF#1, FF#2, etc.), whether they occur simultaneously or consecutively. Transfer data from field notebooks to computer after each survey in case the field notebook is lost. Figure XX is an example of how to record data in the data book.

4 Figure 1: Del Norte County (dn), Crescent City (cc) area nearshore foraging locations: Pyramid Point SMCA (ppc; left) and Crescent City (ccx; right).

5 Figure 2. Humboldt County (hu), Trinidad Head (th) area nearshore foraging locations: Patrick s Point (ppt; left) and Trinidad Bay (trb; right).

6 Figure 3. Humboldt County (hu), Cape Mendocino (cm) area nearshore foraging locations: South Cape Mendocino SMR (cmr; left) and Devil s Gate (dga; right).

7 Figure 4. Mendocino County (me), Kibesillah (ki) area nearshore foraging locations: Kibesillah (kib; left) and Ten Mile SMR (tmr; right).

8 Figure 5. Mendocino County (me), Mendocino Headlands (mh) area nearshore foraging locations: Point Cabrillo SMR (pcr; left) and Mendocino Headlands South (mhs; right).

9 Figure 6. Example of how nearshore foraging and feeding flock data are entered in the field data book.