Biology, Status and Management of Coastal Cutthroat Trout on the North Oregon Coast (Neskowin Creek Necanicum River)

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1 Biology, Status and Management of Coastal Cutthroat Trout on the North Oregon Coast (Neskowin Creek Necanicum River) Prepared by: Oregon Department of Fish and Wildlife North Coast Watershed District Tillamook, Oregon August 23, 2004 Executive Summary As part of the 2005 sport angling regulation development process, the North Coast Watershed District (District) has submitted a proposal to allow retention of coastal cutthroat trout, 2 per day, 8- inch minimum length, in the portion of the zone extending from Neskowin Creek north to the Necanicum River. This proposal is consistent with other angling regulations from Salmon River south to the Oregon/California border. The proposal would continue to restrict retention of coastal cutthroat trout in lower Columbia River tributaries where abundance and trend data were limited. The existing regulation for this portion of the zone has been catch-and-release only for trout since Prior to 1997, regulations for trout angling have ranged from a 2 fish, 12-inch minimum bag limit ( ) to a 5 fish, 8-inch minimum bag in 1993 and earlier. The fishery was restricted to catch-and-release only in 1997 primarily for purposes of conservation. Fishery managers at that time had observed continued declines in abundance of adult Searun Coastal Cutthroat and believed the regulation change was necessary to protect the resource. An improved understanding of coastal cutthroat trout life history relationships, substantial increases in relative abundance of the Searun Cutthroat Trout, and the successful implementation of a consumptive fishery on the mid-coast were the primary basis for proposing re-establishment of the consumptive fishery north of the Salmon River Coastal cutthroat trout populations express several life history forms allowing populations to be resilient and widely distributed. Four life-history types are generally recognized to be present in the District; resident, fluvial, ad-fluvial, and anadromous. Recent research indicates that coastal cutthroat trout populations are structured at the stream or sub-basin level rather than among life history types. Since 1965, ODFW has conducted annual summer snorkel index surveys in the Wilson, Trask, and Nestucca rivers to document abundance of Searun coastal cutthroat trout. Indicators of abundance over the past 6 years show that Searun coastal cutthroat trout have rebounded rapidly from previously observed lows. Peaks in abundance coincide with periods of high ocean productivity over the 39-year survey period. While long-term abundance indices are not available for the other life history components, fish presence surveys conducted by ODFW and others throughout the North Coast basin continues to show resident cutthroat trout widely distributed into the upper reaches of all coastal watersheds.

2 To determine if the proposal was consistent with the Native Fish Conservation Policy (NFCP), the District evaluated what is known about the status and biology of coastal cutthroat trout within the District from Neskowin Creek to the Necanicum River against the interim criteria identified within the policy. Based upon existing empirical information, the District determined that 5 of 6 of the interim criteria (i.e. Populations, Abundance, Habitat Distribution, Reproductive Independence, and Hybridization) had been satisfied. The District has not been able to determine if the proposal satisfies the population productivity criterion because the necessary information is not currently available. However, other indirect evidence strongly suggests that coastal cutthroat trout populations are highly resilient, and productivity of the anadromous form has likely been limited in the past by low ocean survival. The District s analyses relative to the NFCP have been approved by ODFW Conservation and Recovery staff. Migration timing and size distribution of Coho, Chinook, and steelhead juveniles, as determined by the Oregon Plan Life-Cycle Monitoring Project, suggest that these species would not be highly vulnerable to retention or incidental angling mortality associated with the proposed fishery. Most downstream migrating salmonids have left the systems prior to the beginning of the trout fishery in late May. Those fish that remain in the system prior to out migration will be predominately less than 8-inches in length during the time of the proposed fishery. While steelhead par greater than 8- inches (age 2+) may remain in the streams during the proposed fishery, their relative numbers are thought to be very low (less than 5%) in most coastal streams. The trout fishery implemented on the mid-coast in 2001 has been successful from a social and biological perspective, and provides a model for the north coast proposal. Monitoring of coastal cutthroat trout adult Searun abundance and smolt production has been underway for several years prior to the start of that fishery and will continue into the foreseeable future. Early indications suggest that coastal cutthroat smolt abundance has not decreased since the fishery began and adult Searun returns remain healthy. While the proposed fishery on the north coast would be conveniently accessed by Portland and Salem area anglers, as long as other fisheries (ocean salmon, summer steelhead, spring/fall Chinook) remain popular on the north coast, the District believes that the cutthroat fishery will be a relatively moderate intensity fishery. The District has proposed to conduct a non-statistical creel survey should the proposal be adopted. The District has no plans to return to a stream-stock program for coastal cutthroat trout and 1,600 miles (76%) of all coastal cutthroat trout streams will remain closed to trout angling during all or a significant portion of the trout season, allowing them to function as cutthroat trout refugia. Long-term monitoring of the population segment through adult surveys and smolt monitoring will provide the information necessary for the Department to make adaptive management decisions in the future.

3 INTRODUCTION The purpose of this paper is to summarize information on the biology, management history, and status of coastal cutthroat trout in the northern half of the Oregon Department of Fish and Wildlife (ODFW), North Coast Watershed District (Neskowin Creek to Necanicum River) and to identify management implications related to ODFW s proposal to open the coastal cutthroat trout fishery to retention in The proposal submitted by the North Coast Watershed District (District) as part of the 2005 angling regulation review process is presented in Table 1. The purpose of the proposed rule change is to expand opportunity for the retention of trout in the northern portion of the zone where data indicates that coastal cutthroat trout populations are widely distributed and relative abundance of adult anadromous coastal cutthroat trout, the primary life history type that would be targeted by this fishery, have increased substantially in recent years. This proposal is consistent with existing regulations from the Salmon River, south to the Oregon/California border. Because coastal cutthroat trout abundance data for lower Columbia River tributaries is extremely limited, this proposal does not include any portion of the Columbia River or its tributaries. This proposal was one of several proposals submitted by ODFW staff as part of the major angling regulation review process that began in September The Angling Regulation Review Board (ARRB) screened all proposals submitted by staff. The ARRB consisted of public representatives from the Native Fish Conservation Policy Task Force and Warm water Working Group, interested members of the public, Fish Division and Oregon State Police staff, and Fish and Wildlife Commissioners. Proposals that satisfied the screening criteria of the ARRB, were carried forward for public comment from December 1, 2003 through February 29, During that time, additional modifications or new proposals were submitted by the public. This proposal was among those approved by the ARRB to be carried forward for further comment and public review. A series of public meetings were held throughout the state in May 2004 to discuss staff and public proposals that passed the ARRB screening process. Based upon comments received at the public meetings, this proposal was assigned to Category B, meaning that some individuals favored the proposal and some were opposed. A preview of the proposal was given to the Fish and Wildlife Commission in August 2004 with a final decision due in September Table 1. Rule change proposed by North Coast Watershed District staff creating a retention fishery for coastal cutthroat trout in Existing Rule: Northwest Zone Regulations (Page 23), Trout, Catch Limits: Lakes: 5 per day, 2 daily limits in possession. Streams (including tidewaters and bays): Neskowin Creek and north, Catch and release only. Salmon River and south, 2 per day, 2 daily limits in possession Proposed Rule: Northwest Zone Regulations (Page 23), Trout, Catch Limits Lakes: 5 per day, 2 daily limits in possession. Streams (including tidewaters and bays): Neskowin Creek and north, Catch and release only. Salmon River and south, 2 per day, 2 daily limits in possession

4 Lower Columbia tributaries, Catch and Release only. Necanicum River and south (includes Neacoxie/Neawanna), 2 per day, 2 daily limits in possession. BIOLOGY The native range of coastal cutthroat trout corresponds closely with the geographic extent of the Pacific coast rainforest. The northernmost limit of their range is Prince William Sound of southern Alaska. The southern limit is the Eel River of California (Northcote 1997; Sumner 1993). In Oregon, coastal cutthroat trout are found in most coastal streams and lakes. Studies conducted by the Oregon Department of Forestry (ODF) in 1993 indicated that there was an 80% chance of finding coastal cutthroat trout in coastal streams with a drainage basin of greater than 100 acres (Lorensen et al. 1993). Four life history types are generally recognized to be present on the North Oregon Coast; resident, fluvial, ad fluvial, and anadromous (Hooton 1997). Resident coastal cutthroat trout are found throughout the watershed and occupy most headwater and small tributaries. Some resident coastal cutthroat trout may occupy only a few meters of stream habitat until they reach maturity (Northcote 1997). Fluvial coastal cutthroat trout are present in the larger river systems on the north coast such as the Nehalem, Wilson, Trask and Nestucca rivers (Hooton 1997). Fluvial trout may undergo relatively long migrations within these river systems for foraging and reproduction. Ad-fluvial populations are associated with lakes as part of their life cycle. Lakes provide unique foraging and rearing areas not typically associated with fluvial habitats. Anadromous, or sea-run trout are considered to be present in all of Oregon coastal streams that do not have upstream passage barriers (Hooton 1997). In a stock status exercise currently underway, ODFW considers all life-history types of coastal cutthroat trout present in a basin to be components of one diverse population. This management approach is supported by recent evidence that indicates that coastal cutthroat trout populations are structured at the creek or sub-basin level, rather than among individual life history types within a basin (Wenburg and Bentzen 2001). Furthermore, there is evidence to suggest that resident fish may make significant contributions of individuals to the anadromous life history component as demonstrated on the Cowlitz (Dan Rawding, Washington Department of Fish and Wildlife, unpublished data) and Hood rivers (Olsen and French 1997). The diversity present within cutthroat populations allows them to be very resilient and adaptive (Kevin Goodson, ODFW Conservation and Recovery Program, Personal Communication). The following paragraphs provide a very generalized life history for coastal cutthroat trout that is particularly applicable to the resident and anadromous life history types. Coastal cutthroat trout spawn in the smallest tributaries of small and moderate-size streams. They often migrate to the very headwaters of these streams to spawn in reaches often less than a meter wide (Scott and Crossman 1973). Cutthroat spawning tributaries are generally smaller and higher in the watershed than those used by Coho salmon and steelhead. The spawning period for coastal cutthroat trout can extend from December through May. February appears to be the peak spawning period for coastal cutthroat in most Oregon streams. Each female produces 1,000 to 1,200 eggs on the average. Their eggs are much smaller than the eggs of salmon and steelhead. Larger females produce a greater number of larger eggs, and these become larger alevins, which have sizedependent advantages in growth and survival (Sumner 1993).

5 Cutthroat eggs incubate in the spawning gravel for six to seven weeks before hatching. Incubation periods are largely dependent upon stream temperature. Fry quickly move to "lateral habitats" such as slower currents near stream banks, behind rocks or logs and side channels in the stream. The cutthroat fry will stay in the lateral habitats throughout the summer unless they are driven out by larger and more aggressive fish such as Coho salmon fry. Cutthroat fry grow rapidly during their first summer. By September of their first year the cutthroat have grown to two to three inches in length. During their first winter, juvenile cutthroat trout move into off-channel pools and side channels to find relief from the high water flows; however some studies show sub-yearling cutthroat utilizing shallow low-gradient riffles and pool tail outs (Sedell 1984). At one year of age, during their second spring, the parr range throughout the river system, often migrating downstream to the main stem portion of the stream. They feed opportunistically through the summer months on insects, earthworms, crayfish, and sculpin eggs and small fish. With the approach of their second winter, the young cutthroats move back upstream to the protection of the slower current and cover found in the pools and side channels of the tributaries. During their second spring, the older juvenile cutthroat that do not make their first trip to the ocean move downstream into the lower portion of the river. Many times they migrate all the way downstream into the estuary. These areas have abundant food for the young fish to feed on and grow larger prior to ocean migration in some future year. Some of the older juvenile cutthroat trout have been shown to migrate up to 50 miles downstream to the estuary. These parr then migrate back upstream again in the late summer and autumn to reside in the tributaries for the winter. Most juvenile cutthroat trout that migrate to the ocean for the first time (smolts) do so after their third winter. However, this varies considerably. In some streams the majority of juvenile s smolt after the second winter, in others it occurs after the fourth winter. Age one is the earliest and age six is the latest recorded age at which sea-run cutthroat trout have been documented to migrate to salt water for the first time. This movement downstream peaks about a month after the outward migrating spawned-out adults (kelts). While in salt water, juvenile cutthroat trout grow about one inch per month. Predation on juvenile sea-run cutthroat trout is believed to be their major cause of marine mortality. Pacific hakes, spiny dogfish, harbor seals, birds and adult salmon are the most likely marine predators of cutthroat trout. Mortality is greatest for young cutthroat trout entering salt water for the first time. As few as 20% of the fish going to salt water for the first time may survive to return to the stream in the fall (Giger 1972). Adult anadromous cutthroat trout begin to congregate in the estuary and tidal waters of their spawning streams in early summer to prepare for their upstream migration to freshwater. This occurs typically after spending only four to six months in the near-shore ocean environment. Adult sea-run cutthroat trout returning to fresh water from the ocean for the first time measure about 12 to 14 inches in length (Giger 1972). Migration of adult cutthroat trout upstream into freshwater may occur in two or three groups. Those that have spawned previously return to the streams first, usually in late July or early August (Giger 1972). A later group of younger fish typically re-enters freshwater in late August or early September. Not all coastal cutthroat trout returning from the sea for the first time spawn that same year. Few female fish mature sexually before age 4. Sexually immature fish return to the sea the next spring and migrate to fresh water a second time before spawning. This trait is inherited in individual populations, and the percentage of fish exhibiting this behavior varies by

6 geographical area. Details of over-wintering periods for adult cutthroat that have returned to freshwater from the ocean are not documented. Significant weight loss occurs during spawning. One study in Oregon of sea-run cutthroat trout documented approximately 30% to 40% weight loss during the spawning period. Sea-run cutthroat trout withstand the rigors of spawning well. Up to 40% of spawned-out adults (kelts) survive to return to salt water. In Sand Creek, Oregon, in the absence of a fishery, 39% of the cutthroat returned to spawn a second time, 17% spawned a third time and 12% returned a fourth time (Sumner 1993). After spawning, sea-run cutthroat trout kelts migrate downstream generally returning to saltwater within 6 weeks of spawning. MANAGEMENT HISTORY ON THE NORTH COAST Coastal cutthroat trout have provided recreational opportunities for anglers on the north Oregon coast for decades. Records of hatchery releases of coastal cutthroat trout by ODFW date back to 1948; however, there were likely some releases dating back to the early 1900 s when the first hatchery was established in the area. Figure 1 shows the number of hatchery smolts released into the Wilson, Trask, and Nestucca rivers from 1948 through the termination of the coastal cutthroat trout stream-stocking program in the 1990 s. Annual smolt releases ranged from a total of 0 to 22,977 in the Wilson/Trask combined and from 3,112 to 45,663 in the Nestucca River (Figure 1). Release size of smolts was generally between six and nine inches with occasional release size exceeding 12 inches. Most releases were in the main stem river sections; however, on the Nestucca River, several large tributaries were intermittently stocked (e.g. East Beaver Cr. West Beaver Cr., Testament Cr.). Significant numbers of pre-smolts were also stocked throughout these river systems during some years (not included in Figure 1). Occasional stocking of rainbow trout also occurred, but these numbers were far lower than the numbers observed for coastal cutthroat trout. Angling regulations for coastal cutthroat trout have changed considerably over the last several decades. Within the last 15 years, there has been a fundamental shift from a consumptive fishery, dependent on a mix of hatchery and wild fish, to a more conservative catch-and-release fishery that was implemented shortly after stream stocking ended in the early 1990 s. Concerns over conservation and reduced budgets were largely responsible for shifting the trout-stocking program from a stream fishery to lake fishery. Fishery managers believed that stocking trout in lakes would produce a greater yield than had been observed in the stream-stocking program (Keith Braun, District Fish Biologist, Personal Communication). The shift to a catch-and-release fishery in streams was implemented in 1997 for purposes of conservation. Fishery managers had observed continued declines in adult Searun coastal cutthroat for a number of years and believed the regulation change was necessary to protect the resource. At the time, the Searun life history component was managed more as an individual population, rather than as a subset of a larger population(s) that included all life history types. Table 2 summarizes angling regulations for the north coast over the past 10 years. POPULATION STATUS AND TRENDS Given the complex and varied life history patterns exhibited by coastal cutthroat trout, it is difficult to

7 accurately portray populations inclusive of all life history types. Lack of inventory data, other than their range of distribution within the watershed, generally precludes quantitative assessment of the resident life-history type. While resident trout are generally considered to be well distributed throughout the Coast Range (Hooton 1997), little information exists on their relative abundance. Although abundance has not been determined, it is believed that the wide distribution of coastal cutthroat in most streams along the coast indicates a productive and diverse array of populations (Kevin Goodson, ODFW Conservation and Recovery Program, Personal Communication). The adfluvial life history form likely exists in only a few areas within the north half of the North Coast Watershed District. Hooton (1993) reported an isolated population present in Grassy Lake located within the North Fork Nehalem River watershed. Other coastal lakes such as Lytle, Crescent, and Spring lakes may contain, or may have historically contained ad-fluvial populations (Keith Braun, District Fish Biologist, Personal Communication); however, these systems have supported intense hatchery trout fisheries for many years and development pressures have likely impacted habitat. Changes in relative abundance of the adult life stage of the anadromous life history type are more easily quantified for north coast streams. Since 1965, ODFW has conducted annual summer snorkel index surveys in the Wilson, Trask, and Nestucca rivers (Figure 2). Surveys consist of one to four divers (depending on the size of the hole) snorkeling through and enumerating the number of adult anadromous coastal cutthroat trout present. The same holes or reaches within each river system were snorkeled in mid- to late-august of each year. Adult anadromous coastal cutthroat trout were easily distinguishable from resident cutthroat and steelhead smolts based on their size and appearance. Fish counted were typically over 10-inches in length, had a silvery appearance, and lacked the coloration and spotting of resident trout and juvenile steelhead. Table 2. Angling regulations for coastal cutthroat trout from for main stem rivers, and large and small tributaries in North Coast Watershed District Streams from Neskowin Creek and north

8 1XPEHURI&RDVWDO&XWWKURDW7URXW 6PROWV 5HOHDVHG :LOVRQDQG7UDVN5LYHUV &RPELQHG 1HVWXFFD5LYHU <HDU Figure 1. Stocking numbers of hatchery coastal cutthroat smolts (>6 ) in the Wilson/Trask Rivers (combined) and the Nestucca River from 1948 through 1995.

9 YEAR CURRENT Main stems (e.g. Wilson, Trask, Nestucca) Open (Y/N) Y Y Y2 Retention Allowed (Y/N) Y Y N Number of Months Open Bag Limit & (Minimum Size) 5 (8 ) 2(12 ) 2 (12 ) N/A Large Main stem Tributaries (e.g. Beaver Creek, Nestucca Basin) Open (Y/N) Y Y Y2 Retention Allowed (Y/N) Y Y N Number of Months Open Bag Limit & (Minimum Size) 5 (8 ) 2 (12 ) 2 (12 ) N/A Small Tributaries (includes unnamed tributaries) Open (Y/N) Y N N Retention Allowed (Y/N) Y N/A N/A Number of Months Open 5 N/A N/A Bag Limit & (Minimum Size) 5 (8 ) N/A N/A 1 Split season, summer and winter with differing bag and size restrictions 2 Catch and Release Figure 2. Abundance of adult anadromous coastal cutthroat trout in the Wilson and Trask rivers (combined) and the Nestucca River based on ODFW snorkel surveys Abundance Index is based upon number of observations per hole surveyed. Dotted line represents the mean number of observations per hole for the period. Surveys were not conducted in 1975 and 1978 (Wilson River), and 1975, (Trask and Nestucca Rivers). Period of low ocean productivity (warm Pacific Decadal Oscillation, PDO) is identified. Results from snorkel surveys in the Wilson and Trask Rivers indicate that relative abundance of coastal cutthroat trout varies annually (Figure 2). Periods of high relative abundance occurred on the Wilson and Trask Rivers from 1965 through 1973, and 2000 through In the Nestucca River, relative abundance was high in 1965, as well as the 2000 through 2004 period. Abundance of adult anadromous coastal cutthroat trout in all areas was two to ten times higher from 2000 to 2004 than it was during the previous 20-year period. In 2004, abundance indices in all rivers reached an all time high for the survey period. Relative abundance was generally lower in the Nestucca River than in the Wilson or the Trask rivers; however abundance indices in the Nestucca River in 2004 were higher than in the Wilson/Trask combined. In all basins, periods of relatively low abundance coincided with periods of low ocean productivity between Similar trends relative to ocean productivity have been observed for other salmonid stocks, including Coho and steelhead, in the North Coast Basin (Jacobs et al. 2002).

10 While snorkel surveys currently provide the best picture of abundance of adult anadromous coastal cutthroat trout in north coast streams, several factors should be considered when interpreting the results. First, snorkel surveys were initiated primarily for determining relative abundance of spring Chinook salmon in resting holes. As a result, timing of surveys (August) may not necessarily coincide with the peak abundance of coastal cutthroat trout in freshwater. Periods of peak abundance in north coast streams are probably more closely related to changes in stream temperature or the timing of the first late summer or fall freshets (Sumner 1962). Secondly, significant sampling variability may occur as result of changes in water visibility from year to year. This is particularly true in lower river reaches where increased water temperature can result in significant algae blooms during the survey period. Thirdly, in all but the last 10 years, snorkel surveys occurred during years of intense cutthroat trout stocking programs. Observations of these stocked smolts or the returning hatchery progeny from saltwater, would tend to bias the abundance index upward in those years. Lastly, annual changes in stream morphology often decreased the suitability of a hole as coastal cutthroat trout habitat. As a result, some holes were eventually dropped from the survey and others were added (usually within the same reach). In 1998, as part of the Oregon Plan for Salmon and Watersheds, ODFW began monitoring survival and downstream migration of salmonids in coastal basins (Salmonid Life-Cycle Monitoring Project, Solazzi et al. 2002). As a part of this program, one objective was to estimate abundance of downstream migrating juvenile salmonids, including coastal cutthroat trout. Among the coastal basins being evaluated were the Little North Fork (LNF) Wilson River, Little South Fork (LSF) Kilchis River, and the North Fork (NF) Nehalem River. Estimates of the annual number of emigrating coastal cutthroat trout smolts from 1998 through 2004 are provided in Figure 3. Although the data set is limited to a period of seven years, some general trends in coastal cutthroat trout smolt population size are apparent. Peaks in population estimates occurred in 2000 in the LSF Kilchis and NF Nehalem, and in 2001 in the LNF Wilson. Population estimates in 2003 were the second highest observed for the period in the LNF Wilson and the LSF Kilchis, and the third highest observed in the NF Nehalem. In general, abundance of emigrating coastal cutthroat trout smolts was lower in 1998 and 1999 than in other years. This corresponds with the period of low adult returns observed during snorkel surveys (Figure 2). Abundance indices from 2004 were similar to those observed in 2003, except in the LSF Kilchis where numbers declined significantly. MANAGEMENT CONSIDERATIONS AND IMPLICATIONS Implementation of a modest retention fishery has been suggested by recreational anglers to District staff for several years. Until recently, the District was unwilling to propose such a fishery as trends in abundance of adult anadromous coastal cutthroat continued to be on the decline. Adult anadromous cutthroat trout were believed to be the primary life history type that would be targeted by an 8-inch minimum length consumptive fishery during the last half of the trout season (August October). Significant increases in abundance of adult anadromous cutthroat trout over the last several years, and an increased understanding of the coastal cutthroat trout population structure, suggest that a modest retention fishery is warranted; however, other factors need to be considered to ensure that the fishery is sustainable and does not adversely impact non-target fish species. Among those management considerations are questions such as: (1) What will be the geographic extent of the

11 areas open to cutthroat angling and which areas will serve as coastal cutthroat refugia? (2) What other fish species are present during the proposed fishery that could be vulnerable to incidental angling mortality? (3) Would other fish be mistaken for coastal cutthroat trout and be retained as part of the 2 fish, 8-inch minimum bag limit? (4) What has been the result of the retention fishery implemented on the mid-coast? (5) How does the proposal comply with the Native Fish Conservation Policy? and (6) How will coastal cutthroat trout populations and the consumptive fishery be monitored to ensure effective adaptive management in the future? These questions are addressed below: Figure 3. Estimated numbers of emigrating coastal cutthroat trout smolts (>160mm) in the Little North Fork (LNF) Wilson, Little South Fork (LSF) Kilchis, and North Fork (NF) Nehalem rivers, Lack of re-captures of marked fish precluded population estimates for LNF Wilson in (From: Salmonid Life Cycle Monitoring Project). What will be the geographic extent of the areas open to cutthroat angling and which areas will serve as coastal cutthroat refugia? The District s proposal will not open any new waters to cutthroat angling. Areas open in 2004 to catch-and release angling will be the same areas that are proposed to be open to cutthroat retention in Within the portion of the zone from Neskowin Creek to the Necanicum River, there is over 2,100 miles of cutthroat rearing, migration or spawning habitat. This does not include the many miles of 1 st or 2 nd order tributary habitat that hasn t been surveyed or doesn t appear on the GIS database. Approximately 1,600 miles or 76% of these main stem and tributary habitats would remain closed during all or a significant portion of the trout season, allowing them to function as cutthroat trout refugia. While many of the 1,600 miles are smaller-order tributaries supporting primarily resident and pre-smolt coastal cutthroat, many main stem reaches supporting all life history components will be closed as well. These include some main stem reaches of the Nehalem, Nestucca, Little Nestucca, Trask, Wilson, and Kilchis rivers, as well as the entire watersheds of Neskowin Creek, Salmonberry River, Netart s Bay, Ecola Creek, West and East Beaver creeks, Sand Lake Estuary tributaries, Miami River tributaries, Kilchis River tributaries, and several others. What other fish species are present during the proposed fishery that could be vulnerable to incidental angling mortality? By the time the proposed fishery would begin in late May most other salmonid species have already migrated to the estuary or ocean. In smolt out migrant studies on the North Fork Nehalem River from 2000 through 2003, Dalton (Personal Communication) reported that virtually all Coho and steelhead smolts had migrated past the trap site by the end of May (Table 3). Chinook fingerling were the only out migrating species to persist in the system beyond the end of May but even most of those had emigrated by the end of June. Coho, cutthroat, and steelhead fry remain in the systems, but because of their small size or their affinity toward smaller cooler-water tributaries in the late summer, they would likely not be vulnerable to incidental hooking mortality. Some of the larger (age 2+) steelhead parr will not out-migrate to the ocean, but rather rear in the main stem areas during the summer. Monitoring conducted on the Nestucca River in the summers of , indicated that occurrence of these larger steelhead parr were relatively low at less than

12 5% (Steve Trask, Nestucca Rapid Bioassessment, Project Leader, Personal Communication). This observation is confirmed by Busby et al. (1996) who reported that occurrence of age 2+ steelhead in coastal systems is typically below 7% of the pre-smolt population. Another consideration with regard to the proposal is that there currently is a catch-and-release fishery for coastal cutthroat trout in effect on north coast streams. As such, fishery resources have been, and will continue to be exposed to angling mortality from catch-and-release anglers. Any increases in angling mortality would be a function of increased angling pressure, however, only moderate increases in angling pressure were observed when a consumptive trout fishery was opened on the mid coast in 2001 (Bob Buckman, ODFW District Biologist, personal communication). Table 3. Percent of out migrating Coho smolts, steelhead smolts, and Chinook fingerling passing the trap location on the North Fork Nehalem River by the end of May, (Personal Communication, Tim Dalton, Salmonid Life-Cycle Monitoring Project). Species Percent Passing Trap Location Coho smolts 99% 98% 99% 95% Steelhead smolts 100% 95% 99% 99% Chinook fingerlings 58% 35% 12% 24% Would other fish species be mistaken for coastal cutthroat trout and be retained as part of the 2 fish, 8-inch minimum bag limit?: An 8-inch minimum size limit will result in minimal inadvertent retention of fish species other than adult anadromous and resident coastal cutthroat trout. Smolt out migrant trapping by the Salmonid Life-Cycle Monitoring Project (Solazzi et al. 2002) reported that size of emigrating Coho salmon and steelhead smolts in north coast streams is typically below the proposed 8-inch minimum size requirement (Figures 4 and 5). While some steelhead parr over 8- inches (age 2+) will remain in the freshwater system for another year, their numbers are thought to comprise less than 7% of the steelhead pre-smolt population (Busby, et al. 1996). Other species, such as juvenile chum and Chinook salmon, migrate from freshwater as sub yearlings and would not be vulnerable to the fishery. Concerns have been expressed during the public review process that coastal cutthroat smolts will be vulnerable to retention during the proposed fishery. Our evaluation suggests that the fishery will not heavily impact smolting cutthroat trout as most of them will have out migrated prior to the fishery or will be under the 8-inch minimum size requirement. Trotter (1997) reports that most coastal cutthroat smolts are less than 8-inches long at the time of out migration. This is confirmed by smolt out migrant trapping in the Little North Fork Wilson, Little South Fork Kilchis, and North Fork Nehalem rivers that showed that the majority of all cutthroat downstream migrants (including smolts) are less than 8-inches in length (Figure 6) (Personal Communication, Tim Dalton, Salmonid Life-Cycle Monitoring Project, unpublished data).

13 What has been the result of the retention fishery implemented on the mid-coast? In 2001, a retention fishery for coastal cutthroat trout was implemented on the mid-coast (Seesaw River to Salmon River). Prior to the implementation of the retention fishery and for the years following the fishery, researchers have been monitoring population trends of salmonid species as part of several ongoing projects. In the Yachats River Basin, a rapid-bioassessment project documented the number of coastal cutthroat trout per square meter of stream habitat throughout watershed tributaries from 1998 through Results from that research indicates that densities of cutthroat trout have not changed appreciably since implementation of the monitoring program (Figure 7.). Any measurable impacts from implementation of the consumptive fishery would not have begun to manifest themselves until 2002 and Densities in those years did not appear to differ from the pre-harvest period ( ); however, additional monitoring will be needed. Similarly, monitoring of emigrating coastal cutthroat smolts at trap sites on Mill Creek (Siletz), Cascade Creek (Alsea), Upper Lobster Creek (Alsea), and East Fork Lobster Creek (Alsea), as part of the Salmonid Life-Cycle Monitoring Project (Solazzi et al. 2002) showed population levels of coastal cutthroat smolts remaining stable or increasing since implementation of the fishery (Figure 8). Although monitoring has only been in effect for a few years following implementation of the retention fishery, and 2003/2004 are the only years of smolt (2-year old) production since implementation, early results indicate that there has not been any downward trend in smolt production in these basins. These monitoring efforts will provide fishery managers with the information necessary to make adaptive management decisions in the future. As discussed later, similar survey efforts are underway or are planned for the North Coast area. Figure 4. Mean length (mm) of Coho salmon and steelhead smolts at the time of peak migration on the Little North Fork Wilson, Little South Fork Kilchis, and North Fork Nehalem River, (Solazzi et al. 2003) Figure 5. Mean fork length of steelhead smolts greater than 120 (mm) captured at trap sites on the North Fork Nehalem, Little South Fork Kilchis, and Little North Fork Wilson, March though June (From: Salmonid Life Cycle Monitoring Project) Figure 6. Length frequency (mm) of a representative sub-sample of downstream migrating coastal cutthroat trout captured in screw traps Little North Fork Wilson (n=203), Little South Fork Kilchis (n=90), and North Fork Nehalem River (n=176), Figure does not include trout fry less than 60 mm in length. 205 mm equals 8 inches. (From: Salmonid Life Cycle Monitoring Project, Unpublished data). Figure 7. Density (measured as fish per square meter) of coastal cutthroat trout in tributaries of the Yachats River Watershed, (Rapid Bio-assessment project, Steve Trask) Figure 8. Estimated density of emigrating coastal cutthroat trout smolts (>90 mm) in the midcoast basins before ( ) and after ( ) a retention fishery was implemented in Open designation indicates retention is allowed in reach or downstream. Closed designation indicates no consumptive fishery. (From: Salmonid Life Cycle Monitoring Project).

14 How does this proposal relate to the Native Fish Conservation Policy (OAR through )? The intent of the Native Fish Conservation Policy (NFCP) is to provide a basis for managing hatcheries, fisheries, habitat, predators, competitors, and pathogens in balance with sustainable production of naturally produced native fish. One of the areas of emphasis of the NFCP is to ensure that, consistent with native fish conservation, opportunities for fisheries and other societal resource uses are not unnecessarily constrained. While the Native Fish Conservation Policy is intended to be implemented primarily through development of conservation plans for Species Management Units (SMU s), interim guidelines were adopted until conservation plans could be developed (OAR ). Because the NFCP is relatively new, the Department is in the process of identifying SMU s for coastal cutthroat trout. For purposes of this report, the District evaluated what is known about the status and biology of coastal cutthroat trout within the District from Neskowin Creek to the Necanicum River using the interim criteria to determine the health of coastal cutthroat trout populations in this area and to assess whether the proposed fishery would be consistent with the NFCP. We identified populations within the district identical to those currently listed for coastal winter steelhead (Table 4.). The six interim criteria (in italics) and the District s evaluation are listed below. Existing Populations No more than 20% of the historical populations within the species management unit have become extinct and no natural population within the species management unit in existence as of 2003 shall be lost in the future. There is no evidence to indicate that any natural population of coastal cutthroat trout has become extinct within the District. Fish presence/absence surveys conducted by ODFW and others confirm that populations of coastal cutthroat trout still occur throughout all watersheds listed in Table 4. Therefore, the species management unit passes this criterion. The proposed fishery will not harvest coastal cutthroat trout at levels that could cause the extinction on any existing populations. Table 4. Population groupings of coastal cutthroat trout within the North Coast Watershed District from Neskowin Creek north to the Necanicum River 1. Popul Nestucca Description Nestucca River basin plus ocean Trask Wilson Kilchis Lower Nehalem Upper Nehalem Necanicum Trask River plus Tillamook River basins Wilson River basin Kilchis River and Miami River basins Nehalem River basin downstream from Nehalem River basin upstream of, and including, Humbug Creek Necanicum River basin plus ocean tributaries south to Cape Falcon

15 1 Populations are identified for purposes of this report only. As conservation plans are developed for coastal cutthroat trout under the NFCP, population segments and management units will be developed. Habitat Use Distribution - Naturally produced members of a population must occupy at least 50% of a population s historic habitat. Analysis of ODFW s fish distribution and habitat database shows that there are over 2,100 miles of coastal cutthroat migration, spawning, and rearing habitat currently occupied within the District from Neskowin Creek to the Necanicum River. Fish distribution surveys conducted by ODFW and others continue to show occurrence of coastal cutthroat trout into the upper portions of all coastal watersheds, generally to the point where stream gradient precludes further upstream distribution. Even where significant artificial barriers to fish migration may have precluded some life history forms from specific stream reaches (e.g. Barney Dam on the Trask River, McGuire Dam on the Nestucca River), resident populations above these barriers continue to persist. All populations pass this criterion. The proposed angling regulation will not change the present distribution of coastal cutthroat trout. Abundance - The number of naturally produced spawners must be greater than 25% of the average abundance of naturally produced spawners over the most recent 30 year time period. The number of adult anadromous coastal cutthroat trout observed in snorkel surveys from suggests that current abundance exceeds the long-term average (39 years) by two times in the Wilson and Trask, and three times in the Nestucca River. Given the size of the cutthroat observed during these surveys, it is likely that most of these fish are mature spawning anadromous adults (Keith Braun, District Fish Biologist, personal communication). Based on current abundance, these three populations surpass this criterion. Although information is not available for other populations, anecdotal information along the entire Oregon Coast suggests that these populations also exceed this criterion. The District does not anticipate a significant change in relative abundance to occur if the proposed regulation is adopted. Productivity In years when the total spawner abundance is less than the average abundance of naturally produced spawners over the past 30 years, and then the rate of population increase shall be at least 1.2 adult offspring per parent. Where offspring are defined as naturally produced adults that survive to spawn and parents are defined as those adults of both natural plus hatchery origin that spawned and collectively produced the observed offspring. There is no empirical evidence available within the District to accurately describe productivity of coastal cutthroat trout populations. Snorkel surveys conducted in the Wilson, Trask, and Nestucca Rivers from , suggest that spawner abundance of the anadromous form fell below the 39-year average during the early 1970 s to the late 1990 s. Despite the low relative abundance during that time period, populations persisted in all watersheds and rebounded quickly concurrent with improved ocean conditions, suggesting that productivity may have been limited by low ocean survival. The Department will need to develop an effective approach to assessing coastal cutthroat trout productivity in the near future. Reproductive Independence At least 90% of the spawners within a population must be naturally produced and not hatchery produced fish, unless the department determines the hatchery-produced fish are being used in a short-term experimental program to help restore a population in its natural habitat or otherwise directed by a court order. The last introduction of hatchery-produced coastal

16 cutthroat trout in the District occurred in Given that coastal cutthroat trout seldom live beyond 7-8 years (Trotter 1997), it is safe to conclude that the current population of coastal cutthroat trout in the District are of natural origin and pass this criterion. The proposed regulation change will not affect reproductive independence. Hybridization - The occurrence of individuals that are the product of deleterious hybridization with species that are non-native to the basin in which they are found must be rare or nonexistent. The potential for deleterious hybridization between coastal cutthroat trout and other species that are nonnative to basins within the zone is considered to be low to none. Hybridization has been reported to occur between coastal cutthroat and steelhead, and coastal cutthroat and rainbow trout in basins outside of the District (Hawkins 1997; Johnson et al. 1997). Out-of-basin stocks of steelhead and rainbow trout within the District are currently limited to hatchery Siletz-origin summer steelhead, Alsea-origin winter steelhead, and lake-stocked (Cape Cod origin) rainbow trout. There has been no documentation of hybridization between cutthroat trout and steelhead in 6 years of trapping on the North Fork Nehalem, Little South Fork Kilchis, and Little North Fork Wilson rivers (Tim Dalton, Salmonid Life-Cycle Monitoring Project, Personal Communication). With the exception of a few anecdotal reports from Lake Lytle, where rainbow stocking occurs, no reports of hybridization between coastal cutthroat and hatchery stock rainbow trout have been documented (Keith Braun, North Coast Watershed District Fish Biologist, Personal Communication). Hybridization will not occur as a result of the proposed regulation change. How will coastal cutthroat trout populations and the consumptive fishery be monitored to ensure effective adaptive management in the future? ODFW will continue to monitor coastal cutthroat trout populations at juvenile and adult life stages to allow for implementation of adaptive management. In addition, if the proposed angling regulation is adopted, we will conduct a creel survey on selected rivers to assess angler effort and catch rates. Our proposed monitoring framework is as described below: Oregon Plan Salmonid Life-Cycle Monitoring Project: The Oregon Plan Salmonid Life-Cycle Monitoring Project will continue to operate downstream migrant traps at the North Fork Nehalem River, Little South Fork Kilchis River, and Little North Fork Wilson River into the foreseeable future. In addition, a proposal to operate an adult and juvenile trap on the East Fork Trask River is under consideration. This project provides the information necessary to determine the size distribution and relative abundance of downstream migrating coastal cutthroat trout and other salmonids. The District will work with research staff to assess in-season migrant numbers and continue to monitor changes in annual abundance. Snorkel Surveys to determine relative abundance of adult coastal cutthroat trout: ODFW s adult resting hole snorkel surveys will continue on the Wilson, Trask, and Nestucca rivers into the foreseeable future. These surveys began in 1965 and provide an excellent resource for assessing long-term trends in relative abundance of adult coastal cutthroat trout, particularly the anadromous life history form. 3 or more snorkelers will conduct surveys in August of each year. Indices will be evaluated at the end of each survey period to determine changes in relative abundance from previous years. While the anadromous life history form represents only one component of coastal cutthroat trout populations, we will utilize a conservative management approach and consider fishery restrictions should this population segment fall consistently below long-term averages.

17 ODFW Western Oregon Rearing Project: The Western Oregon Rearing Project was designed primarily for determining status and trends of coastal Coho salmon. However, enumeration of juvenile coastal cutthroat during these surveys provides insight relative to their geographic distribution and may be useful in identifying broad changes in densities over long time scales. This project was initiated in 1998 and is planned to continue for the foreseeable future. The District will continue to work with research staff to evaluate survey data and describe trends in distribution and densities. Conduct Rapid Bioassessment Project in Tillamook Bay Watersheds: As part of an USFWS grant proposal submitted by the Tillamook Estuaries Partnership, a rapid-bioassessment survey will likely be conducted in some Tillamook Bay streams in The rapid bioassessment project consists of snorkel surveys conducted in a subset of pool habitats within entire stream reaches. While primarily designed for determining densities of juvenile Coho salmon, coastal cutthroat trout will also be enumerated as part of the sampling protocol. Information collected on coastal cutthroat trout will be used to describe their relative densities in pool habitats and to further assess their geographic distribution within the District. Identifying the upper extent of fish use in coastal watersheds: ODFW will continue to work with private landowners, as well as State and Federal landowners to identify the range of fish distribution in coastal watersheds. These surveys are conducted primarily for determining fish presence, predominately coastal cutthroat trout, for proposed forest operations: however, they are another tool for determining the geographic distribution of coastal cutthroat trout within the District. Initiate a non-statistical creel survey in selected coastal basins: If the proposed angling regulation is adopted, ODFW will initiate a non-statistical creel survey in selected coastal basins. The purpose of the survey will be to assess angler effort and catch rates during selected periods throughout the trout season. These surveys will focus primarily on weekend days, including the trout opener, from May through October. Information collected will help fishery managers to determine the intensity of the fishery, the distribution of anglers within the watershed, the trout life history types being harvested, and estimate the angler catch per unit effort. We will also be able to identify the proportion of anglers practicing catch-and-release, as well as gear types being used in the fishery. Survey effort will be dependent upon staff availability and budgetary constraints. CONCLUSIONS Coastal cutthroat trout populations express several life history forms. This allows populations to be resilient and widely distributed. Indicators of abundance of anadromous coastal cutthroat trout on the north coast suggest that the population segment is rebounding from lows observed over the previous 20 years. Although not demonstrated with scientific rigor, there is some indication that previous trends in low abundance were due, in part, to periods of low ocean productivity. Given the success of the coastal cutthroat trout retention fishery on the mid-coast from a social and biological perspective, the Department believes that a modest harvest of these fishes on the north coast is justifiable. The District has no plans to return to a stream-stock program for coastal cutthroat trout and most streams will remain closed to trout angling. Long-term monitoring of the population segment through adult surveys and smolt monitoring will provide the information necessary for the