Jarvisetal bsb movements_01_mar10


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Jarvisetal bsb movements_01_mar10

  2. 2. 6 Abstract 7 During the 1960s and 1990s, the California Department of Fish and Game tagged 8,634 8 barred sand bass in southern California. Tag and recapture data suggest migrant individuals reside 9 at spawning grounds for approximately one month. Although 64% of non-spawning season10 recaptures occurred within 1 km of the spawning location, the average (± SD) recapture distance of11 migrant fish was 13 ± 8 km. Fish size (TL) was weakly correlated with “migration” distance from12 spawning locations (rs(57) = 0.31, p = 0.02). Spatial and temporal trends in recaptures suggest a13 high degree of spawning and non-spawning season site fidelity. 2
  3. 3. 14 Introduction15 Barred sand bass, Paralabrax nebulifer, continues to be one of the most sought-after sport fish16 in southern California. In the early 1900s, barred sand bass were landed in both the commercial17 and recreational fisheries; however, due to limited demand in the commercial fishery and scarcity18 of the resource during the 1950s, commercial take was banned in 1953 and a 12 in (30.5 cm)19 minimum size limit was implemented in 1959 (Collyer 1949; Young 1969). Since the 1960s,20 barred sand bass have ranked among the top 10 sport fish caught by commercial passenger fishing21 vessels (CPFVs = party boats) in southern California, with total annual catches averaging nearly22 two million fish per year between 1980 and 2003* (Allen and Hovey 2001; PSMFC 2010a).23 Although no commercial fishery currently exists for barred sand bass in California, “heavy annual24 landings” of barred sand bass have been reported in the commercial fisheries of Baja California,25 Mexico, and the Gulf of Mexico in recent years (Aburto-Oropeza et al. 2008).26 In southern California, fishing effort for barred sand bass by both party and private boaters is27 highest during peak spawning season (June to August). In recent years, approximately 77% of the28 June, July, and August barred sand bass harvest was taken by party/charter boats (PSMFC 2010b).29 Well-known spawning aggregation sites include the Ventura Flats, inner Santa Monica Bay,30 Huntington Beach Flats, San Onofre, and Silver Strand in San Diego. According to California31 Department of Fish and Game (CDFG) CPFV logbook data, Huntington Beach Flats ranks the32 highest in numbers of barred sand bass caught in the past 40 years (CDFG unpublished data).33 From 1961 to 2008, barred sand bass CPFV catch-per-unit-effort (CPUE = barred sand bass34 kept/angler*hr) increased to a high in 2000, and has recently decreased to the lowest CPUE since * Data reported were collected by the Marine Recreational Statistics Survey (MRFSS), which was replaced in 2004 by the California Recreational Fisheries Survey (CRFS). Catch estimates after 2003 were not included because data from these two surveys are not comparable. 3
  4. 4. 35 1985 (CDFG unpublished data), causing concern regarding the vulnerability of the population to36 future harvest impacts.37 Fish species that are targeted during their spawning aggregations are especially susceptible to38 overexploitation because harvest effects may not be immediately evident (Sadovy and Domeier39 2005). Furthermore, overexploitation of an aggregate spawner can result in the complete absence40 of spawning aggregation formations at historic sites (Domeier and Colin 1997; Sadovy and41 Domeier 2005). Consequences of this occurring in the barred sand bass fishery might include42 negative ecological impacts, as well as severe economic impacts to the sport fishing industry in43 southern California.44 Barred sand bass is one of three temperate serranine fishes (sea basses), including kelp45 bass, Paralabrax clathratus, and spotted sand bass, Paralabrax maculatofasciatus, that participate46 to varying degrees in aggregate spawning behavior (Hovey and Allen 2000; Erisman and Allen47 2006; Miller and Allen 2006). Barred sand bass breeding aggregations are reported to occur over48 sand flats in depths of 20 to 40 m (Turner 1969; Feder et al. 1974; Love et al. 1996), and based on49 the exceptionally high landings of barred sand bass during the summer, it is possible that these50 aggregations consist of thousands of fish. However, underwater video documentation of these51 aggregations has never been reported. Following peak spawning, considerably fewer barred sand52 bass are caught over the sand flats and catches typically resume inshore in bays or near low relief53 natural or artificial reefs, but not in such high numbers (Love et al. 1996). These catch trends may54 suggest transient spawning aggregation behavior, in which large aggregations form at specific,55 predictable locations at higher than average densities for a period of several weeks to months56 (Domeier and Colin 1997). Transient spawning aggregations are characterized by having57 individuals that migrate relatively longer distances to breed than “resident” aggregate spawners, 4
  5. 5. 58 but it is still unclear to what degree this may occur with barred sand bass. Knowledge of the59 origins and destinations of barred sand bass spawning migrations, and understanding whether all or60 some of the adult population participates in spawning aggregations will be important for effective61 management of this species.62 In the 1960s and 1990s, biologists with the California Department of Fish and Game (CDFG)63 tagged nearly 9,000 barred sand bass in southern California. The recapture information from these64 two time periods enables us to document the historical spawning-related movements of barred65 sand bass for the first time. Specifically, our objectives of this study are to examine these66 historical data for trends in 1) residency at spawning locations, 2) movement to and from spawning67 locations, and 3) breeding site fidelity.6869 Methods70 Tagging Effort71 During the 1960s and 1990s, barred sand bass were tagged along the coast of southern72 California and at one location in Baja California, Mexico (Figure 1). Tagging locations included73 sand flats, reefs, and bay habitat. During both tagging periods, fish were captured by hook-and-74 line, measured to the nearest mm total length (TL), externally tagged with spaghetti or T-bar tags,75 and released. In the 1990s, fish were also captured by bottom trawl, and upon release, tagged fish76 suffering from barotrauma were recompressed to depth using milk crates. Loran or GPS77 coordinates of the tagging sites were recorded; otherwise, a site name or geographic landmark was78 provided. In addition, depth (m) and release condition were recorded for some but not all fish.79 Rewards for recaptures of tagged fish were offered during both tagging periods. Recapture 5
  6. 6. 80 information included date, location, TL (mm), and tag ID number. In the 1990s, recapture depth81 (m) and Loran or GPS coordinates were also provided when available.82 Analysis83 All historical barred sand bass tag and recapture data were archived into a relational84 database for analysis. To standardize tagging effort across the two tagging periods, locations for85 all records were assigned a fishing site code based on historical southern California CPFV sport86 fish surveys (Ally et al. 1990). Spawning season codes were also assigned to each tag and87 recapture record based on capture month (Nov.–Mar. = non-spawning season, Apr.–May = early88 spawning season, Jun.–Aug. = peak spawning season, Sept.–Oct. = late spawning season). Days at89 liberty, recapture distance (estimated or actual km), and general direction of movement were90 calculated and incorporated into the database. Recapture distances were measured as linear91 distances between approximate or actual tagging and recapture locations. In this paper we report92 recapture rates and return rates. Recapture rates refer to the number of fish recaptured at a given93 site divided by the total number fish recaptures. Return rates refer to the number of fish recaptured94 at a given site divided by the total number of fish tagged at that site.95 Spawning season residency 96 To investigate the residence time of individuals at spawning locations, we selected fish 97 tagged at Huntington Beach Flats during peak spawning season and recaptured at Huntington 98 Beach Flats within the same year (peak spawning season through December). This location was 99 chosen because of the high return rate and due to the relatively high historical catch numbers of100 barred sand bass. For each group of fish tagged in June, July, and August, we plotted the101 cumulative number of tag returns over time (days at liberty), as well as the frequency of recaptures102 over time. Each trend line was examined for the point in time after which the rate of tag returns 6
  7. 7. 103 decreased; this point was assumed to represent the minimum residence time. We also report the104 locations and recapture distances of fish that were recaptured away from Huntington Beach Flats105 during the same peak spawning season.106 Movement to non-spawning season locations107 Movement from peak spawning season tagging locations to non-spawning season recapture108 locations was assumed to be movement from spawning grounds to non-spawning season109 residences. To estimate the proximity of non-spawning season residences to spawning grounds,110 we grouped non-spawning season recapture distances for fish tagged during peak spawning season111 into 5 km bins. We then calculated the average non-spawning season recapture distances from112 each tagging location to determine whether non-spawning season “migration” distances varied by113 spawning location. Finally, we tested for a relationship between fish length (TL) and “migration”114 distance to non-spawning season residences using a Spearman Rho rank test.115 Movement to spawning locations116 We examined peak spawning season recaptures of fish tagged in Newport Bay during the117 non-spawning season to identify if and where Newport Bay residents migrate to spawn. Spawning118 “migration” distances from Newport Bay to spawning grounds were reported and also tested for a119 relationship with fish length (TL) using a Spearman Rho rank test. Lastly, we looked for seasonal120 patterns in site fidelity to Newport Bay by creating a recapture plot of fish tagged in Newport Bay121 (Nov.-May) for the years 1964 to 1973.122 Spawning and non-spawning season site fidelity123 To investigate annual site fidelity of barred sand bass to specific peak spawning season124 tagging locations (i.e., presumed spawning grounds) we considered fish that were only tagged125 during peak spawning season and recaptured during subsequent peak spawning seasons. We 7
  8. 8. 126 constructed a matrix of the number of fish recaptured by tagging location and recapture location,127 with tag and recapture locations arranged from N to S. A higher number of recaptures that occur128 along a series of corresponding tag/recapture locations within the matrix (i.e., where recapture129 location = tag location) indicates a higher degree of spawning site fidelity than an arrangement of130 non-corresponding tag/recapture locations or few corresponding tag/recapture locations within the131 matrix.132133 Results134 Tagging Effort135 From 1962 to 1976 barred sand bass were tagged from Santa Barbara to San Diego Bay (Table136 1, Figure 2a). Most of this tagging effort occurred in the 1960s. Thirty-eight percent were tagged137 at Huntington Beach Flats during peak spawning season (Jun.–Aug.), while 21% were tagged in138 Newport Bay during the non-spawning season and early spawning season (Nov.–May). Tagging139 at other locations primarily occurred during peak spawning season. Between 1989 and 1999,140 barred sand bass were tagged from Santa Barbara to Baja California, including Santa Catalina141 Island (Table 1, Figure 2b); 20 of these locations had also been visited in the 1960s. In the 1990s,142 50% of fish were tagged at Huntington Beach Flats (32%) and Horseshoe Kelp, mostly during143 peak spawning season. Most fish were captured by hook-and-line, while others were captured by144 trawl (Table 1). Tagging effort (= average number of fish tagged per day and average number of145 tagging months per year) was similar between the two tagging periods (Table 1), although in the146 1990s, most of the tags were out within the first four years, versus six years in the 1960s. 8
  9. 9. 147 Demographics of tagged barred sand bass148 Length frequency distributions of tagged fish were similar at locations with the highest149 numbers of tagged fish (Manhattan Reef, Horseshoe Kelp, Huntington Beach Flats, and Newport150 Bay, Figure 3). On average, fish tagged in the 1990s were larger than fish tagged in the 1960s151 (Table 1), although this trend was likely influenced by the larger fish tagged in Ventura and152 Mexico in the 1990s (Figure 3). The majority of fish tagged in Ventura were captured by trawl,153 with no difference in capture depth between line-caught and trawl-caught barred sand bass (Table154 1). There was a weak but significant positive linear relationship between capture depth and TL (r2155 = 0.14, p = 0.001).156 Most tagged fish were greater than the size at 100% maturity (~ 270 mm); however, the157 proportion of legal sized (= 305 mm) barred sand bass was higher in the 1990s than the 1960s158 (Table 1). In the 1990s, the proportion of tagged adults decreased from 88% in the non-spawning159 season to 59% in the late spawning season; likewise, the proportion of tagged legal fish decreased160 from 65% to 38%. This trend was also apparent for fish tagged in the 1960s, but was less161 pronounced.162 Recaptures163 Despite similar tagging effort between the two tagging periods, recaptures were more164 numerous in the 1960s than the 1990s (Table 1, Figure 4a,b). In the 1960s, locations with the165 highest recapture rates were Huntington Beach Flats (29%) and Newport Bay (16%; Figure 4a).166 Return rates at these locations were 13% (n = 231) and 22% (n = 224), respectively. In the 1990s,167 Huntington Beach Flats again had the highest number of recaptures (49%; Figure 4b); however tag168 returns at this site were relatively low (6%) compared to the 1960s. The 1990s had fewer long169 term recaptures (> 90 days at liberty) than the 1960s, with the majority of recaptures (75%) 9
  10. 10. 170 occurring within just 63 days at liberty compared with 315 days in the 1960s (Figure 5). Although171 the maximum days at liberty were similar between the two tagging periods (Table 1), there was a172 significant difference in the average number of days at liberty between the 1960s and the 1990s173 (student t-test, t = 7.156, p = 0.000; Table 1). Overall, the majority of recaptures occurred within174 close proximity (< 10 km) to the site of tagging, although one recapture occurred 92 km S (Los175 Alamitos to Oceanside). It is not clear how many recaptured fish were released versus how many176 were kept.177 Spawning season residency178 We identified 117 Huntington Beach Flats same-year returns in the 1960s and 55 in the179 1990s. The rate of returns for fish tagged during peak spawning season decreased after180 approximately 34 days at liberty, regardless of tagging month (Figure 6). This period accounted181 for 73, 93, and 80% of June-, July-, and August-tagged fish returns, respectively. Subsequently,182 return rates of July-, and August-tagged fish both decreased by 88%. In contrast, the decrease in183 the return rate for June-tagged fish was more gradual (40%). This gradual decrease was attributed184 to a subsequent increase in the frequency of June-tagged fish returns that occurred between 46 and185 55 days at liberty (Figure 6); these returns occurred during the month of August. The maximum186 number of days at liberty was greatest for August- (119 days) and June-tagged fish (77 days),187 compared to only 56 days for July-tagged fish.188 Fifteen fish tagged at Huntington Beach Flats during peak spawning season were189 recaptured at a different location during the same peak spawning season; recapture locations for190 these migratory fish included Horseshoe Kelp (n = 9), Seal Beach (n = 1), Santa Ana River Jetty (n191 = 3), Corona Del Mar (n = 1), and Dana Point (n = 1). Most of these migratory fish (13 of 15)192 were tagged in July. 10
  11. 11. 193 Movement to non-spawning season locations194 Non-spawning season recapture distances were variable among individuals, with some195 suggesting resident behavior and others demonstrating migratory behavior. There were 59 barred196 sand bass that were tagged during peak spawning season and recaptured during non-spawning197 season (1960s, n = 50; 1990s, n = 9). The frequency distribution of recapture distances revealed198 an interesting trend, with 64% of fish being recaptured within 1 km of the tagging site; the199 remainder showed a normal distribution around 15 km (Figure 7). In the 1960s, the overall200 average (±SD) non-spawning season recapture distance was 4 ± 7 km, but fish recaptured greater201 than 1 km away from the tagging location had an average recapture distance of 13 ± 8 km. In the202 1990s, eight of nine fish were recaptured greater than 1 km away from the tag site; the average203 non-spawning season recapture distance was 19 ± 14 km. Fish size (TL) showed a weak, positive204 correlation with non-spawning season “migration” distance (rs(57) = 0.31, p = 0.02).205 Carlsbad and Huntington Beach Flats tag locations had the highest number of recaptures206 occurring during non-spawning season, but fish tagged at Huntington Beach Flats showed higher207 variability in recapture distances (Table 2). The farthest non-spawning season recapture distances208 occurred between Ventura and Carbon Canyon (40 km S) and Tijuana, Mexico and La Jolla (35209 km N). The farthest non-spawning season recapture location from Huntington Beach Flats was the210 Palos Verdes Peninsula (29 km N). Most non-spawning season recapture locations were located211 north of peak spawning season tagging locations (Table 2).212 Movement to spawning locations213 Fish tagged in a presumed non-spawning season residence (Newport Bay) during non-214 spawning season were primarily recaptured outside of Newport Bay during peak spawning season215 (Table 4). We identified at least 15 different peak spawning season recapture sites that were 11
  12. 12. 216 typically located south of Newport Bay by an average (±SD) distance of 17 ± 15 km (Table 3). No217 fish were tagged in Newport Bay during non-spawning season in the 1990s; however, a fish tagged218 in San Diego Bay during non-spawning season was recaptured during peak spawning season off219 the coast of San Onofre (75 km N). In contrast to the correlation results reported above, no220 correlation was found between fish size (TL) and “migration” distance from Newport Bay to221 spawning grounds (rs(71) = 0.23, p = 0.05).222 Spawning and non-spawning season site fidelity223 Several fish were tagged during peak spawning season and recaptured during subsequent224 peak spawning seasons (1960s, n = 162; 1990s, n = 7). Eighty-nine percent of these recaptures225 occurred after 1 yr at liberty, 8% after 2 yr, and 2% after 3 yr. Of the 169 recaptures, 80%226 occurred back at the same tagging location. The average recapture distance (±SD) for the 20%227 that were recaptured elsewhere was 18 ± 16 km. Overall, the recapture matrix plot identified a228 high degree of breeding site fidelity as indicated by the arrangement of recaptures occurring along229 corresponding tag/recapture locations (Figure 8). Tagging locations with the highest measure of230 breeding site fidelity appeared to be Huntington Beach Flats, Ocean Park Venice, San Onofre231 Power Plant, Carlsbad, and Twintrees; however, these return rates may be biased by differences in232 fishing and tagging effort across sites. We also identified two fish that were twice recaptured in233 subsequent peak spawning seasons at the same locations (Twintrees and Huntington Beach Flats,234 Table 4).235 Annual trends in Newport Bay recaptures revealed fish were still present and/or had left236 and returned to Newport Bay during subsequent non-spawning and early spawning seasons (Figure237 9). Two fish were twice recaptured at Newport Bay over subsequent non-spawning seasons (Table 12
  13. 13. 238 4). Fish recaptures outside of Newport Bay typically occurred during the middle of peak spawning239 season through late spawning season (Figure 9).240241 Discussion242 Spawning season residency243 The spawning residency of migrant barred sand bass at Huntington Beach Flats appears to244 be approximately one month. This is within the reported spawning residency for other fishes (4 –245 80 days; Robichaud et al. 2003; Bendal et al. 2005; Douglas et al. 2009). For some species,246 spawning residency may vary by year and by sex, but we were unable to test this for barred sand247 bass. Nevertheless, individual barred sand bass with shorter-term residency (e.g., up to one248 month) likely represent migratory individuals, while fish demonstrating longer-term residency249 (e.g., up to four months) likely represent fish whose home ranges are located within or near to250 Huntington Beach Flats. Fish tagged in June or August (the beginning and end of peak spawning251 season) demonstrated longer-term residency to the spawning grounds than fish tagged in July,252 suggesting the peak in spawning migrations occurs in July. This timing is in agreement with the253 month of highest catch numbers and fishing effort for barred sand bass in the southern California254 CPFV fishery (CDFG unpublished data). Moreover, the majority of fish that were recaptured255 away from Huntington Beach Flats during peak spawning season were tagged in July. Finally, the256 expected peak in immigration/emigration rates and associated fishing pressure was apparent in the257 frequency of June-tagged returns over time. For example, return rates of June-tagged fish258 decreased after a month and then subsequently increased again before leveling off. We attribute259 this initial decrease to a peak in immigration to the spawning grounds occurring some time in July,260 while the subsequent increase and leveling off in return rates is likely associated with a peak in 13
  14. 14. 261 emigration from the spawning grounds, followed by an associated decrease in fishing pressure262 there.263 Due to the use of standard tag and recapture methods, we were unable to quantify diel site264 fidelity at spawning locations. Barred sand bass individuals may use neighboring reefs to “rest” or265 forage between spawning events or may travel to and from other nearby spawning locations during266 this period. Actively tracked coral trout, Plectropomus leopardus, an aggregate spawning267 Epinephelid (= Serranidae in part; Smith and Craig 2007), were shown to make multiple trips268 between their home ranges and nearby spawning sites (< 1 km) during the spawning season (Zeller269 1998). Zeller (1998) also reported that in some cases, visits to spawning grounds occurred270 multiple times during the day or lasted from two to three days. Several large artificial reefs and271 structures located near Huntington Beach Flats include Bolsa Chica Artificial Reef (2.7 km W), oil272 platforms Eva (2.7 km NW), Emma (2.3 km NE), and Esther (6.7 km NW), and the Los Angeles273 Federal Breakwater (11.8 km NW). Data collected by the California Seafloor Mapping Program274 (CSMP) reveal patches of hard substrate (i.e., smaller patch reefs or structures) also exist within275 the Huntington Beach Flats area (CSUMB 2009). Increases of barred sand bass densities during276 peak spawning season have been observed on SCUBA at Platform Eva (Martin 2008) and the Los277 Angeles Federal Breakwater (Froeschke et al. 2005). The degree to which these reefs/structures278 may act as reproductive staging areas for migratory individuals, resting/foraging areas during peak279 spawning season, or even distinct spawning areas, remains unknown.280 Movement to and from spawning locations281 Movement to and from spawning locations is perhaps one of the more interesting and yet282 least known behaviors of barred sand bass. Our results further suggest that some barred sand bass283 individuals migrate to spawn, while others are year-round residents. Mason (2008) demonstrated 14
  15. 15. 284 that a portion of acoustically monitored adult barred sand bass at Santa Catalina Island, CA,285 exhibited year-round site fidelity to their home ranges, while others were not detected in these286 areas during spawning season. This type of “polymorphic movement behavior” has been287 described for other aggregate spawners including coral trout, Nassau grouper, Epinephelus288 striatus, and snapper, Pagrus auratus (Colin 1992; Zeller 1998; Egli and Babcock 2004).289 Not every fish migrated to the same location after spawning season. Likewise, barred sand290 bass that shared a non-spawning season residence (Newport Bay) did not necessarily migrate to the291 same spawning grounds. Zeller (1998) reported that coral trout with overlapping home ranges did292 not necessarily make excursions to the same spawning grounds, regardless of spawning ground293 proximity to home ranges. Spawning migration distance has been strongly linked to body294 condition, size-at-age/maturity, and fishing pressure in Atlantic cod (Gadus morhua; Jørgensen et295 al. 2008); fish that migrate longer distances are generally older, bigger fish with higher overall296 fitness. Although a relationship between fish size (TL) and “migration” distance in this study was297 inconclusive, we can not rule out bioenergetics as a possible explanation for the observed298 variability in migration distances, as maturity and fitness were not determined for tagged fish.299 Moreover, it is impossible to know for certain the accuracy of the reported fish tag and recapture300 locations or if some fish were early or late spawners/migrators. These caveats, in addition to the301 possibility that a portion of the adult barred sand bass population simply doesn’t spawn (i.e.,302 practices “skipped spawning”), may explain the variability in reported migration distances303 (Jørgensen et al. 2005).304 Spawning and non-spawning season site fidelity305 Most fish tagged during peak spawning season were recaptured at the same location during306 subsequent peak spawning seasons. Whether these individuals represent year-round residents or 15
  16. 16. 307 repeat migrants, barred sand bass appear to show a high degree of breeding site fidelity.308 Historically, breeding site fidelity was studied extensively in salmonids, but less so in other fishes.309 With the advent of more sophisticated tracking methods (e.g. electronic tags), breeding site fidelity310 in fishes has been increasingly documented (Hunter et al. 2003; Block et al. 2005; Douglas et al.311 2009). Tradition (or learned behavior) has been shown to play a primary role in spawning site312 selection over annual reassessment of resources, especially if resources are relatively unchanging313 from one year to the next (Warner 1988, 1990). Due to annual differences in tagging effort across314 tagging locations, it was not possible to accurately quantify long-term inter-annual variability in315 spawning site fidelity by tagging location. Recaptures that occurred at different locations in316 subsequent years may reflect individual variability in the timing of spawning-related movements,317 movement among aggregation sites, or a certain degree of annual reassessment.318 We also identified individuals that demonstrated site fidelity to a non-spawning season319 tagging location (Newport Bay). Bays are noted as habitat for young-of-the year (YOY) and320 juvenile barred sand bass (Feder et al. 1974; Valle et al. 1999; Allen et al. 2002), while adults321 prefer sand/rock ecotone habitat to 30 m depth (Feder et al. 1974; Johnson et al. 1990; Mason322 2008). In San Diego Bay, YOY barred sand bass were shown to develop there throughout their323 life history and adults utilized the bay habitat throughout the year (Pondella et al. 2006). In this324 study, a fish that was tagged and recaptured during non-spawning season in Newport Bay may325 represent a fish that remained there year-round or one that migrated to spawn and returned in the326 winter. Our data indicate that a portion of adult barred sand bass in Newport Bay migrate to327 locations outside of the bay during spawning season. This identifies Newport Bay as an important328 non-spawning season residence for barred sand bass, as well as an important source of migrants to329 various spawning locations outside of the bay. Although it is unknown for certain whether the 16
  17. 17. 330 migrant recaptures in this study would have returned to Newport Bay following peak spawning331 season, the overall pattern in recaptures is highly suggestive.332 Recapture rates333 The most striking difference between the two tagging periods is the recapture rate: 17% in334 the 1960s compared to 4% in the 1990s. A typical range of recapture rates using standard tag and335 recapture methods is 3 to 10% (Lowe and Bray 2006). Given that tagging effort and numbers of336 tagged fish did not dramatically differ between these two time periods, recapture rates may have337 been influenced by changes in barred sand bass availability, in addition to advances in fishing338 technology (e.g., fish finders, GPS), the willingness of fishers to report tag returns, and an339 increased knowledge of spawning aggregation sites. In general, high recapture rates in open340 systems reflect relatively lower population sizes due to the higher probability of encountering the341 same fish at a later date. This may explain the higher number of long-term recaptures in the 1960s342 dataset. CPFV barred sand bass catch values were nearly four times greater in the 1990s than in343 the 1960s despite only a doubling of fishing effort (CDFG unpublished data). Historical Fish and344 Game publications report that barred sand bass were scarce during the 1950s (a cold water period)345 and occurred more frequently along the coast “in and subsequent to periods of warmer waters”346 (Young 1969; Feder et al. 1974). Kelp bass and barred sand bass larvae densities were also lower347 during the cool regime (1950s – 1970s) and higher in the warm regime (1980s – 1990s), especially348 during the 1980s (Moser et al. 2001). While it appears that barred sand bass populations may have349 increased in the 1990s relative to the 1960s, barred sand bass stock-recruitment relationships and350 the effects on these relationships by natural and anthropogenic influences remain unknown. 17
  18. 18. 351 Management implications352 Currently, a sustainable level of harvest for barred sand bass is unknown because no353 biomass estimates exist. Due to concerns over barred sand bass catch declines in recent years and354 the uncertainty in the status of the population, barred sand bass may require further fishery355 protection beyond current minimum size limits and bag limits. Information gathered on the356 spawning-related movements of barred sand bass may be useful for identifying further protection357 measures. For instance, an aggregate spawner that demonstrates multiple spawning events over a358 relatively long spawning residency period would likely benefit from a series of temporary fishing359 closures during the peak in fishing effort. Non-spawning residences that are shown to supply360 migrant spawners to spawning aggregation sites may be important sites to consider for seasonal361 protection of barred sand bass. Further consideration of barred sand bass movement patterns and362 life history traits, in addition to important feasibility concerns, may help to define additional363 alternatives to protect barred sand bass until a harvest guideline can be developed.364365 Acknowledgements366 CDFG lead investigators for the barred sand bass tagging studies in the 1960s and 1990s367 were P. “Bud” Young and J.R. Raymond Ally, respectively. Over the two tagging periods, CDFG368 tagging efforts were augmented by [and listed in no particular order] R. Izor (Izorline369 International), Orange County Marine Institute, County Sanitation Districts of Orange County, Los370 Angeles Rod and Reel Foundation, and many other individual volunteers. We thank L.G. Allen371 and T. Mason for their critical review of the drafts of this manuscript. Funding was supported in372 part by the Los Angeles County Fish and Game Commission and the Federal Aid in Sportfish373 Restoration Act (also known as the Dingell-Johnson Act; Grant #F-50-R-20). 18
  19. 19. 374 Literature Cited375 Aburto-Oropeza, O., B. Erisman, V. Valdez-Ornelas, and G. Danemann. 2008. Commercially376 Important Serranid Fishes from the Gulf of California: Ecology, Fisheries, and Conservation.377 Ciencia y Conservación 2008:1-23.378 Allen, L.G., and T.E. Hovey. 2001. Barred sand bass. Pp. 224-225 in Californias Living Marine379 Resources: A Status Report (W.S. Leet, C.M. Dewees, R. Klingbeil & E.J. Larson, eds.),380 Calif. Fish Game Resources Agency, 592 pp.381 Allen, L.G., A.M. Findlay, and C.M. Phalen. 2002. Structure and standing stock of the fish382 assemblages of San Diego Bay, California from 1994 to 1999. Bull. So. Cal. Acad. Sci.,383 1012:49-85.384 Ally, J.R.R, D.S. Ono, R.B. Read, M.D. Harris, and M. Wallace. 1990. Southern California385 Partyboat Sport Fish Survey: Procedures Manual. Calif. Fish Game Resources Agency, 130386 pp.387 Bendall, B., A. Moore, and V. Quayle. 2005. The post-spawning movements of migratory brown388 trout, Salmo trutta L. J. Fish Biol., 67:809-822.389 Block, B.A., S.L.H. Teo, A. Walli, A. Boustany, M.J.W. Stokesbury, C.J. Farwell, K.C. Weng, H.390 Dewar, And T.D. Williams. 2005. Electronic tagging and population structure of Atlantic391 bluefin tuna. Nature, 434:1121-1127.392 Collyer, R.D. 1949. Rockbass. Pp 113-115 in The commercial fish catch of California for the393 year 1947 with an historical review 1916-1947. Calif. Fish Game, Fish Bull., 74.394 [CSUMB] California State University, Monterey Bay. 2009. 2008 CSMP Surveys: San Diego to395 Point Conception. (1 December, 2009; http://seafloor.csumb.edu). 19
  20. 20. 396 Domeier, M.L., and P.L. Colin. 1997. Tropical reef fish spawning aggregations: defined and397 reviewed. Bull. Mar. Sci., 60:698-726.398 Douglas, S.G., G. Chaput, J. Hayward, and J. Sheasgreen. 2009. Prespawning, spawning, and399 postspawning behavior of striped bass in the Miramichi River. Trans. Am. Fish. Soc.,400 138:121-134.401 Egli, D.P. and R.C. Babcock. 2004. Ultrasonic tracking reveals multiple behavioural modes of402 snapper (Pagrus auratus) in a temperate no-take marine reserve. ICES J. Mar. Sci.,403 61:1137-1143.404 Erisman, B.E. and L.G. Allen. 2006. Reproductive behavior of a temperate serranid fish,405 Paralabrax clathratus, from Santa Catalina Island, California, U.S.A. J. Fish Biol., 68:157-406 184.407 Feder, H.M., C.H. Turner, and C. Limbaugh. 1974. Observations on fishes associated with kelp408 beds in southern California. Calif. Fish Game Fish Bull., 160:31-32.409 Froeschke, J.T., L.G. Allen, and D.J. Pondella. 2005. The reef fish assemblage of the outer Los410 Angeles Federal Breakwater, 2002-2003. Bull. So. Cal. Acad. Sci., 104:63-74.411 Hovey, T.E. and L.G. Allen. 2000. Reproductive patterns of six populations of the spotted sand412 bass, Paralabrax maculatofasciatus, from Southern and Baja California. Copeia, 2000:459-413 468.414 Hunter, E., J.D. Metcalfe, and J.D. Reynolds. 2003. Migration route and spawning area fidelity415 by North Sea plaice. Proc. R. Soc. Lond. B, 270:2097-2103.416 Johnson, T.D., A.M. Barnett, E.E. DeMartini, L.L. Craft, R.F. Ambrose, and L.J. Purcell. 1994.417 Fish production and habitat utilization on a southern California artificial reef. Bull. Mar. Sci.,418 55:709-723. 20
  21. 21. 419 Jørgensen, C., B. Ernande, Ø. Fiksen, and U. Dieckmann. 2006. The logic of skipped spawning in420 fish. Can. J. Fish. Aquat. Sci., 63:200-211.421 Jørgensen, C., E.S. Dunlop, A.F. Opdal, and Ø. Fiksen. 2008. The evolution of spawning422 migrations: state dependence and fishing-induced changes. Ecology, 89:3436-3448.423 Love, M.S., A. Brooks, and J.R.R. Ally. 1996a. An analysis of commercial passenger fishing424 vessel fisheries for kelp bass and barred sand bass in the southern California Bight. Calif. Fish425 Game, 82:105-121.426 Love, M.S., A. Brooks, D. Busatto, J. Stephens, and P. Gregory. 1996b. Aspects of the life427 histories of the kelp bass, Paralabrax clathratus, and barred sand bass, P. nebulifer, from the428 southern California Bight. U.S. Fish. Bull., 94:472-481.429 Lowe, C.G., and R.N. Bray. 2006. Movement and activity patterns. Pp. 524-553 in The Ecology430 of California Marine Fishes (L.G. Allen, M.H. Horn, and D.J. Pondella, eds.), University of431 California Press, 670 pp.432 Martin, C.J.B. 2009. San Pedro Shelf platform fish assemblages and relations to habitat quality.433 Master’s Thesis. California State University Long Beach.434 Mason, T. 2008. Home range size, habitat use, and the effects of habitat breaks on the movements435 of temperate reef gamefishes in a southern California marine protected area. Master’s Thesis.436 California State University Long Beach. 52 pp.437 Moser, H.G., R.L. Charter, P.E. Smith, D.A. Ambrose, W. Watson, S.R. Charter, and E.M.438 Sandknop. 2001. Distributional atlas of fish larvae and eggs in the Southern California Bight439 region: 1951-1998. Calif. Coop. Oceanic Fish. Invest. Atlas, 34:46.440 [PSMFC] Pacific States Marine Fisheries Commission. 2010a. Recreational Fisheries441 Information Network (RecFIN) Estimated Total Catch with Releases (A+B1+B2) in 21
  22. 22. 442 Thousands of Fish Caught By Marine Recreational Anglers By Species and Year For All443 Modes of Fishing in All Marine Areas in Southern California where Common Name444 Contains Barred Sand Bass. (20 January, 2010; www.recfin.org)445 PSMFC. 2010b. RecFIN Estimated Total Harvested Dead Catch (A+B1) in Thousands of Fish446 Caught by Marine Recreational Anglers Fishing for All Possible Species by Month and State447 Fishing Mode for All Modes Of Fishing in All Marine Areas in Southern California from448 January 2004 - December 2008 where Common Name Contains Barred Sand Bass. (1449 February, 2010; www.recfin.org)450 Pondella, D.J., L.G. Allen, M.T. Craig, and B. Gintert, B. 2006. Evaluation of eelgrass mitigation451 and fishery enhancement structures in San Diego Bay, California. Bull. Mar. Sci., 78:115-452 131.453 Robichaud, D. and G.A. Rose. 2003. Sex differences in cod residency on a spawning ground.454 Fish. Res., 60:33-43.455 Sadovy, Y. and M.L. Domeier. 2005. Are aggregation-fisheries sustainable? Reef fish fisheries as456 a case study. Coral Reefs, 24:254-262.457 Sadovy, Y. and M.L. Domeier. 2005. Perplexing problems of sexual patterns in the fish genus458 Paralabrax. J. Zool. Lond., 267:121-133.459 Sala, Enric, O. Aburto-Oropeza, G. Paredes, and G. Thompson. 2003. Spawning aggregations460 and reproductive behavior of reef fishes in the Gulf of California. Bull. Mar. Sci.,72:103-461 121.462 Smith, W. and M.T. Craig. 2007. Casting the Percomorph net widely: the importance of broad463 taxonomic sampling in the search for the placement of Serranid and Percid fishes. Copeia,464 1:35-55. 22
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  24. 24. 478 Table 1. Tag and recapture summary statistics for barred sand bass tagged in southern California,479 historical California Department of Fish and Game tagging project (1960s and 1990s). Tag and recapture results 1960s 1990s Tagged fish 4,687 3,947 Tagging effort days 174 153 fish/day 27 ± 32 26 ± 58 Avg (±SD) (mo/yr) 4±3 6±3 Capture method hook-and-line 100% 74% bottom trawl -- 26% Avg (±SD) capture depth (m) overall -- 15 ± 17 hook-and-line -- 22 ± 7 bottom trawl -- 25 ± 12 Avg (±SD) TL (mm) 306 ± 38 337 ± 72 % mature 89% 93% % legal size 41% 70% Recaptures 801 171 Return rate overall 17% 4% hook-and-line 17% 5% bottom trawl -- 3% Avg (±SD) recapture depth (m) -- 23 ± 9 Avg (±SD) TL (mm) 326 ± 43 343 ± 46 % mature 96% 98% % legal size 68% 86% Days at liberty Avg (±SD) 200 ± 197 90 ± 187 Max 1,211 1,258 Recapture distance (km) Avg (±SD) - All fish 6 ± 12 7±9 Avg (±SD) - Only movers 18 ± 15 10 ± 9 Max 92 76480 24
  25. 25. 481 Table 2. Recapture distances (km) of barred sand bass tagged during peak spawning season482 (Jun-Aug) and recaptured during non-spawning season (Nov-Mar), historical California483 Department of Fish and Game tagging project (1960s and 1990s). Dir. = direction of recapture484 location from tagging location.485 25
  26. 26. 486 Table. 3. Recapture distances (km) of barred sand bass tagged in Newport Bay during the non-487 spawning season (Nov-Mar) and recaptured during peak spawning season (Jun-Aug), historical488 California Department of Fish and Game tagging project (1960s). Dir. = direction of recapture489 location from tagging location.490 Recapture distance (km) Peak Spawning Season Recapture Location N Avg Stdev Dir. Horseshoe Kelp 1 24.1 -- W Huntington Beach Flats 13 17.6 2.2 W Santa Ana River Jetty 3 8.0 0.0 W Newport Harbor 19 0.5 1.5 -- Corona Del Mar 2 2.4 1.1 S Crystal Cove 1 1.6 -- S North Laguna Beach 3 10.2 1.9 S South Laguna Beach 1 12.9 -- S Salt Creek 2 18.5 1.1 S Dana Point 6 20.4 1.3 S Capistrano Beach 1 24.1 -- S San Mateo Point 4 31.4 1.6 S San Clemente 1 29.0 -- S Middle Kelp 1 24.1 -- S San Onofre Power Plant 5 32.8 0.9 S Barn Kelp 8 42.8 1.5 S Oceanside 1 51.5 -- S 26
  27. 27. 491 Table 4. Tag and recapture dates and locations of barred sand bass recaptured on two separate occasions, historical California492 Department of Fish and Game tagging project (1960s).493494495 * Asterisks denote fish that were released in Newport Harbor following weigh-in at a fishing tournament. 27
  28. 28. 496 List of Figures497498 Figure 1. Map of barred sand bass tagging locations in southern California, historical California499 Department of Fish and Game tagging project (1960s and 1990s).500501 Figure 2. Numbers of barred sand bass tagged by the California Department of Fish and Game502 in southern California during the a) 1960s and b) 1990s.503504 Figure 3. Length-frequency distributions of barred sand bass by tagging location, historical505 California Department of Fish and Game tagging project (1960s and 1990s). 1960s and 1990s506 sites are represented by grey and white bars, respectively. Only locations where at least 100507 tagged individuals are listed. The vertical lines represent minimum size of legal take (305 mm).508509 Figure 4. Numbers of tagged barred sand bass recaptured during the a) 1960s and b) 1990s,510 historical California Department of Fish and Game tagging project (1960s and 1990s).511512 Figure 5. Numbers of barred sand bass recaptured by days since tagged for fish tagged in the a)513 1960s and b) 1990s, historical California Department of Fish and Game tagging project (1960s514 and 1990s).515516 Figure 6. Cumulative number of barred sand bass recaptures (dots) and frequency of recaptures517 (bars) by days since tagged for fish tagged during each month of peak spawning season (June, 28
  29. 29. 518 July, August) at Huntington Beach Flats, CA and recaptured within the same year at the same519 location, historical California Department of Fish and Game tagging project (1960s and 1990s).520521 Figure 7. Recapture distances for barred sand bass tagged during peak spawning season (Jun-522 Aug) and recaptured during non-spawning season (Nov-Mar), historical California Department523 of Fish and Game tagging project (1960s and 1990s). 1960s = dark bars, 1990s = grey bars.524525 Figure 8. Recapture matrix plot of barred sand bass tagged during peak spawning season and526 recaptured in subsequent peak spawning seasons, historical California Department of Fish and527 Game tagging project (1960s and 1990s). Shaded, darker boxes occurring along the diagonal528 line indicate a higher degree of breeding site fidelity.529530 Figure 9. Recapture plot of barred sand bass tagged in Newport Bay, California during non-531 spawning season (Nov-Mar, shaded areas), historical California Department of Fish and Game532 tagging project (1960s). Recaptures occurring within 90 d of tagging were excluded. Recapture533 locations are arranged north to south (top to bottom). 29
  30. 30. 534535 Figure 1. 30
  31. 31. 536537538 Figure 2. 31
  32. 32. 539540 Figure 3. 32
  33. 33. 541542543 Figure 4 33
  34. 34. 544545 Figure 5. 34
  35. 35. 546547548 Figure 6. 35
  36. 36. 549550 Figure 7. 36
  37. 37. 551552 Figure 8. 37
  38. 38. 553554 Figure 9. 38