WIOMSA-CORDIO spawning book Full Doc 10 oct 13.pdf

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which shelved gently ( ca. 25 o ) to the reef edge at (ca. 15-16 m) (Fig. 2), where it dropped steeply toover 30 m. The reef slope was high in relief with ledges, caves and overhangs. The site was boundedby a reef pass to the north and a continuous reef slope to the south. E. fuscoguttatus were observedaggregating along the upper reef edge near the overhangs and caves, and also on the upper, moreopen reef slope at depths of ca. 12-18m. Exploratory surveys beyond the southern boundary on theFeb 2010 new moon located 2 males and 1 female (see Table 1 for visual identification of sexes).Fig. 2. KM spawningaggregation sitea) drawing used asdatasheet for recordingnumbers and behaviourof fish, b) GISmap from digitisedGPS readings of theperimeter, contoursand site features.The KW site ranged from 14-20 m in depth and had high reef rugosity with several large bommiesand pinnacles. The top of the reef further inshore was ca. 11-12 m depth and sloped gently seawardto a sand-rubble bottom. The site was bordered to the north by a sand channel reef break thatextended to shore. Strong currents characterised the channel. The core area where E. fuscoguttatuswere concentrated was estimated to be around 500 m 2 and the total area of the site ca. 2000 m 2 .66
Verification and size of spawning aggregationsRelatively high numbers of E. fuscoguttatus were observed from November 2009 to February2010 at KM, with maximum monthly estimates ranging from 16 to 32 (Fig. 3). Fewer data wereavailable for KW with an estimated 14 and 8 E. fuscoguttatus observed during December andJanuary, respectively (Fig. 3). Numbers of E. fuscoguttatus at KM in July and August, the wintermonths and putatively the non-spawning season, were lower, particularly in August when only 3fish were observed. By contrast, a maximum of 13 fish was recorded in July (Fig. 3). We calculateda mean non-spawning density at KM of 6.0 fish (±2.5 SE) during these winter months, thoughsample size was limited (n= 4 counts). Based on published criteria (at least 4-fold, Domeier 2012),24 fish would therefore constitute a spawning aggregation of E. fuscoguttatus at this site. Countsfrom November to February (LD 28-2) ranged from 10 to 32 (n=9, mean of 21.3 ±2.6 SE) andaggregation size exceeded the threshold in 3 consecutive months (Dec-Feb). Smaller numbers werepresent in November and through the reproductive season, characteristic of a build up in numbersat an aggregation site prior to spawning (Fig. 3).Fig. 3. Seasonal pattern in abundance of E. fuscoguttatus at KM (triangles) and KW (circles) spawning aggregationsites. Data are the total counts from single daily UVC surveys at KM (ca. 2,744 m 2 ) and at KW (ca. 2000 km 2 ). Thedashed line represents minimum abundance (24 fish) that constitutes an aggregation at KM based on criterion of atleast a 4-fold increase in density (see main text).Daily counts plotted against lunar day indicate that E. fuscoguttatus aggregations formed aroundthe new moon (Fig. 4). A gradual increase in the numbers at KM was observed just prior to thenew moon with peak numbers corresponding to LD 1. Aggregation number abruptly decreasedon LD 2 and 3, suggesting fish were departing the site. Surveys were not conducted throughouta lunar cycle; however, lower numbers of fish were observed during the full moon period (Fig.4). Insufficient data were collected from KW to determine seasonal or lunar patterns. Changes inaggregation abundance throughout the day were not apparent, though data were few (Fig. 5).67
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The designation of geographical ent
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Chapter 1: IntroductionJan Robinson
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limited, subsistence levels of expl
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NTRs for spawning aggregations usin
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al. 2003). Verification may include
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a fraction of spawning sites are pr
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Chapter 3: Targeted fishing of the
Page 23 and 24: verifying spawning aggregations, we
Page 25 and 26: ecorded from inshore close to the c
Page 27 and 28: (a)(b)Fig. 3. Spatial patterns ofca
Page 30 and 31: pooled sizes of the three spawning
Page 32 and 33: found S. sutor contributed up to 44
Page 34 and 35: 2011b). However, observations of fi
Page 36 and 37: MethodsTo identify seasonal and lun
Page 38 and 39: n=199Females GSI (mean ± SE)2.521.
Page 40 and 41: The estimate of size at maturity in
Page 42 and 43: This study was designed to verify S
Page 44 and 45: were selected. Fish selected for ta
Page 46 and 47: The number of traps increased on th
Page 48 and 49: Of the 9 tagged fish detected by re
Page 50 and 51: Fig. 7. Diel patterns ofdetection f
Page 52 and 53: Spawning aggregation site fidelity
Page 54 and 55: Chapter 6: Shoemaker spinefoot rabb
Page 56 and 57: anterior of the anus and below the
Page 58 and 59: A high percentage (80.8%) of depart
Page 60 and 61: arrivals and departures at these tw
Page 62 and 63: are typically applied for reef fish
Page 64 and 65: (a)(b)(c)Chapter 3, Figure 3. Spati
Page 66 and 67: (1)(2)(3)(4)(5)(6)Chapter 7, Table
Page 68 and 69: Chapter 12, Fig. 1 Fraction of fema
Page 70 and 71: Plates 8. Selected photographs from
Page 72 and 73: MethodsStudy sitesThe study area wa
Page 76 and 77: Fig. 4. Lunar periodicity in number
Page 78 and 79: Behaviour and appearanceDescription
Page 80 and 81: eported aggregations forming betwee
Page 82 and 83: The sizes of E. fuscoguttatus aggre
Page 84 and 85: Materials and methodsStudy area and
Page 86 and 87: TL. All fish tagged were considered
Page 88 and 89: Lunar timing of arrivals and depart
Page 90 and 91: Fig. 8. The presence and absence of
Page 92 and 93: aggregation fishing. This critical
Page 94 and 95: Chapter 9: Persistence of grouper (
Page 96 and 97: ResultsBetween 2003 and 2006, the c
Page 98 and 99: Fig. 2. Mean (± standard error, SE
Page 100 and 101: A few species (e.g. Epinephelus gut
Page 102 and 103: (a)(b)Fig. 1. Map of (a) study site
Page 104 and 105: Fig. 2. Number of E. lanceolatus ob
Page 106 and 107: was having any impact on the popula
Page 108 and 109: A spawning aggregation is said to o
Page 110 and 111: Chapter 11: Evaluation of an indica
Page 112 and 113: Table 1 Aggregation fisheries asses
Page 114 and 115: the lists of Jennings et al. (1999)
Page 116 and 117: with the more vulnerable labrids an
Page 118 and 119: The remaining serranid populations
Page 120 and 121: Spawning aggregation behaviour is c
Page 122 and 123: tiger grouper, Mycteroperca tigris:
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of protecting the normal residence
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• Since grouper males are afforde
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Fig. 2 Yield-per-recruit normalized
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The approaches identified above are
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during full moon periods. Siganus s
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model, many parameter estimates are
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ReferencesAbunge C (2011) Managing
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Cox DR (1972) Regression models and
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Grüss A, Kaplan DM, Hart DR (2011b
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Kaunda-Arara B, Rose GA (2004a) Eff
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Newcomer RT, Taylor DH, Guttman SI
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Sancho G, Petersen CW, Lobel PS (20
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Appendix 1. QuestionnaireMASMA SPAW
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8. Spawning aggregation knowledgeUs
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Example items KSh Furthest site Clo
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Appendix II. Experimental testing o
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Clove oil concentrationAt a concent
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Appendix III. Application of acoust
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