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Hudson Canyon Shelf Tilefish Habitat Areas

Hudson Canyon Shelf Tilefish Habitat Areas. Vincent G. Guida US Dept. of Commerce NOAA, NMFS, NEFSC J.J. Howard Lab 74 Magruder Rd. Highlands, NJ 07732. Hudson Canyon. SW Tilefish Habitat.

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Hudson Canyon Shelf Tilefish Habitat Areas

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  1. Hudson Canyon Shelf Tilefish Habitat Areas Vincent G. Guida US Dept. of Commerce NOAA, NMFS, NEFSC J.J. Howard Lab 74 Magruder Rd. Highlands, NJ 07732

  2. Hudson Canyon SW Tilefish Habitat

  3. Hudson Canyon Habitat Area of Particular Concern (HAPC) in relation to Tilefish Habitat areas Outer Shelf NE Tilefish Habitat Slope SW Tilefish Habitat Modified after: EFH Omnibus Amendment Draft Environmental Impact Statement (DEIS), Phase I Maps of Habitat Areas of Particular Concern (HAPC) Alternatives, NEFMC, 2007.

  4. 2001-2004 Sites where tilefish burrows were seen in Seaboss transects NE Tilefish Habitat Known gravel areas SW Tilefish Habitat

  5. The SW Tilefish Habitat includes the 10’ Square block from which the largest commercial catches have been made. 73º W Annual tilefish catch from 10’ Square block #397244 72º W Annual Catch (lbs.) HUDSON CANYON: depth contours in yellow 40º N 80 m 10 min. Latitude block 200 m N 500 m SW Tilefish Habitat 10 min. Longitude block 39º N 2001 Commercial Catch Data: NMFS Northeast Regional Office

  6. Subadult tilefish (Lopholatilus chamaeleonticeps): 40 cm TL, 0.68 kg: caught in 36’ otter trawl, Station BD4 (39º 17.67’N, 72º 21.78’W), 191m depth: Cruise DE05-14, 11/02/05, 20:36 UTC

  7. IMAGES OF TILEFISH BURROWS FROM THE SW TILEFISH HABITAT AREA taken by USGS Seaboss aboard NEFSC Benthic Habitat Cruises in 2001, 2002, and 2004.

  8. WX-6 #10 DE04-12 8/27/04 20:05:13 UTC 39º 28.6431’ N 72º 21.6855’ W 136.7 m 20 cm Photo: USGS Chain Dogfish over Tilefish Burrow Complex in Clay with Galatheid Crabs

  9. IJ1 #34 DE01-11 10/31/01 01:08:22 UTC 39º 26.772’ N 72º 25.674’ W ~125 m Photo: USGS Tilefish burrow in muddy sand 10/30/01 20:08:22 local

  10. IJ4 #24 DE01-11 10/31/01 04:24:52 utc 39º 22.926’ N 72º 18.155’ W ~170 m Photo: USGS 10/30/01 23:24:52 local Yellowfin bass Anthias nicholsi nestling in tilefish burrow

  11. BD4 #16 DE01-11 11/02/01 00:31:50 UTC 39° 18.076’N 72° 21.314’W ~197 m Photo: USGS 11/01/01 19:31:50 local Unidentified fish nestling in old tilefish burrow complex

  12. BD8 #8 DE01-11 11/02/01 03:48:42 UTC 39° 20.864’N 72° 28.111’W ~136 m Photo: USGS 11/01/01 22:48:42 local Partially collapsed tilefish burrow complex with Cancer sp. crab

  13. KL4 #4 OC02-12 10/28/02 ~193 m 20 cm Photo: USGS Tilefish burrow complex in clay with sunken Sargassum thallus

  14. KL4 #20 OC02-12 10/28/02 ~193 m Photo: USGS Tilefish burrow complex in clay

  15. IJ0 #12 OC02-12 10/29/02 ~116 m Photo: USGS Unidentified fish and galatheid crabs in tilefish burrow complex in muddy sand

  16. IJ0 #25 OC02-12 10/29/02 ~115 m Photo: USGS Tilefish burrow complex in muddy sand with Astropecten americanus

  17. WX7 #24 DE04-12 8/27/04 20:12:25 UTC 39º 28.6447’ N, 72 º 21.7587’ W 134.3 m 20 cm Photo: USGS Tilefish burrow complex in clay

  18. WX7 #30 DE04-12 8/27/04 20:16:59 UTC 39º 28.6521’ N, 72 º 21.8165’ W 134.4 m 20 cm Photo: USGS Tilefish burrow complex in clay with galatheid crab

  19. Tilefish stock management, habitat conservation, and the their role in ecosystem fisheries management will require better stock assessment techniques and a clear understanding of the role of tilefish as habitat engineers. • Some Observartions & Questions: • Net avoidance has made accurate fisheries-independent stock assessment of tilefish via Survey Trawls virtually impossible. Can their numbers be assessed by means of visualizing their burrows or via ultra high-resolution acoustic methods? Can active/inactive burrows be distinguished? • How are burrows distributed on a small scale within a habitat, e.g. spacing and clustering patterns, patch density, etc. Very limited side scan sonar data suggests that there are distinct non-random patterns. • Observations (preceding photos) suggest that tilefish can excavate burrows in a variety of sediment types. How are burrows distributed with respect to substrate type. • Observations also suggest that the importance of habitat engineering by tilefish may depend on the nature of the substrate; burrow complexes surrounding tilefish burrows in firm clay appear to be larger and supporting more secondary excavations than those in muddy sand. Is this true, and how does this influence the roles of tilefish in differing habitats?

  20. NEBO Hudson Canyon Tilefish Habitat Investigation Objectives Objectives: 1. Utilize Habcam high resolution side scan sonar in concert with synoptic visual imagery to test acoustic methods for assessing tilefish burrow density, including distinguishing active and inactive burrows, and distribution patterns on scales of meters and on scales of km (i.e. stock assessment improvement). 2. Utilize Habcam high resolution side scan sonar in concert with synoptic visual imagery to assess the degree of secondary burrowing and the identity of secondary burrow inhabitants and other predators associated with tilefish excavations (i.e. community support issues). 3. Utilize Habcam high resolution side scan sonar in concert with synoptic visual imagery and sediment characterization to determine the role of sediment characteristics in the distribution and intensity of both primary and secondary burrows (ecosystem level issues).

  21. Rationale for use of Habcam 1. The characteristics of tilefish burrows are best assessed visually, but burrows are spaced sufficiently far apart that few can be seen in a typical video/photo transect (e.g. 20 min. Seaboss deployment) 2. Tilefish have never been observed in their burrows with Seaboss because the fish are photophobic and easily escape a vehicle that typically moves at about 0.5 kt. Judgments with regard to what burrows are active or inactive have therefore been made based on wall condition and the presence of a cloud of sediment in the central burrow, presumably resulting from the rapid egress of the resident tilefish. 3. Due to wider swath width, many more burrows can be seen with side scan sonar than visually, but geolocation with typical side scan equipment in not accurate enough to make comparison of acoustic and visual images of the same burrow. Such comparison is necessary to develop an acoustic assessment method. 4. Habcam’s side scan capability, its more rapid speed for towing Habcam (2+ kt.) and longer deployment, its ability to simultaneously obtain overlapping photo and sonar images allow for the possibilities of acoustic imaging of enough burrows to see local distributional patterns, actually seeing tilefish in their burrows, and obtaining simultaneous acoustic and visual images of the same burrows to determine how to use acoustic imagery to distinguish such features as active/inactive status and the intensity and extent of secondary burrowing.

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