Hudson Canyon Shelf Hudson Canyon Shelf Tilefish Habitat AreasTilefish Habitat Areas

Vincent G. Guida US Dept. of Commerce NOAA, NMFS, NEFSC

J.J. Howard Lab 74 Magruder Rd.

Highlands, NJ 07732

Hudson Hudson CanyonCanyon

SW Tilefish SW Tilefish HabitatHabitat

Hudson Canyon Hudson Canyon Habitat Area of Habitat Area of Particular Particular Concern (HAPC) Concern (HAPC) in relation to in relation to Tilefish Habitat Tilefish Habitat areasareas SW SW

Tilefish Tilefish HabitatHabitat

Outer Shelf

Slope

NE Tilefish NE Tilefish HabitatHabitat

Modified after: EFH Omnibus Amendment Draft Environmental Impact Statement (DEIS), Phase I Maps of Habitat Areas of Particular Concern (HAPC) Alternatives, NEFMC, 2007.

39.2

39.3

39.4

39.5

39.6

39.7

39.8

-72.9 -72.8 -72.7 -72.6 -72.5 -72.4 -72.3 -72.2 -72.1 -72.0

Station locations

Approx limits of USGS multi-beam coverage

LEGEND

Possible gravel areas from USGS multibeam chart

Station where tilefish burrows were seen

80

80

100

120

140

500

1000

160200

100

120 140160

200

500

1000

UV3

BD4

BD3

BD2BD1

IJ4

IJ3

IJ2

IJ1

HG1

HG2

HG3HG4

BD8

S

IJ5

BD5

PR2

PR1

ST3

ST2

ST1

ST4

IJ0

KL4KL3

KL2

KL0

KL1

MN4MN3

MN2

MN1

BD0

BD00

S*UV1

Hudson Canyon

Y4

Y5

Y6

PR4PR5

PR31

OUTER SHELF

CONTINENTAL SLOPE

INNER SHELF

N

6 nmi = 11.1 km

UV00

WX3

UV0UV2

UV4

UV5

UV6

WX1

WX2

WX4

WX5

WX6

WX7

KL5

Known gravel areas

SW Tilefish SW Tilefish HabitatHabitat

NE Tilefish NE Tilefish HabitatHabitat

2001-2004 Sites where tilefish burrows were seen in Seaboss transects

12

34

56

6

5

4

3

2

1

0

100,000

200,000

300,000

Tilefish Catch by 10' Squares

80 m

200 m

500 m

HUDSON HUDSON CANYON: CANYON: depth contours depth contours in yellowin yellow

2001 Commercial Catch Data: NMFS Northeast Regional Office

N

Annual tilefish catch from 10’ Square block #397244

SW Tilefish SW Tilefish HabitatHabitat

Annual Catch (lbs.)

10 min. Longitude block

10

min

. Lat

itu

de

blo

ck

39º N

40º N

72º W

73º W

The SW Tilefish Habitat includes the 10’ Square block from which the The SW Tilefish Habitat includes the 10’ Square block from which the largest commercial catches have been made.largest commercial catches have been made.

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

IMAGES OF TILEFISH BURROWS FROM THE SW TILEFISH HABITAT AREA taken by USGS

Seaboss aboard NEFSC Benthic Habitat Cruises in 2001, 2002, and 2004.

WX-6 #10 DE04-12 8/27/04 20:05:13 UTC 39º 28.6431’ N 72º 21.6855’ W 136.7 m

Chain Dogfish over Tilefish Burrow Complex in Clay with Galatheid Crabs

20 cm

Photo: USGS

IJ1 #34 DE01-11 10/31/01 01:08:22 UTC 39º 26.772’ N 72º 25.674’ W ~125 m

10/30/01 20:08:22 local Tilefish burrow in muddy sand

Photo: USGS

IJ4 #24 DE01-11 10/31/01 04:24:52 utc 39º 22.926’ N 72º 18.155’ W ~170 m

10/30/01 23:24:52 local Yellowfin bass Anthias nicholsi nestling in tilefish burrow

Photo: USGS

BD4 #16 DE01-11 11/02/01 00:31:50 UTC 39° 18.076’N 72° 21.314’W ~197 m

11/01/01 19:31:50 local Unidentified fish nestling in old tilefish burrow complex

Photo: USGS

BD8 #8 DE01-11 11/02/01 03:48:42 UTC 39° 20.864’N 72° 28.111’W ~136 m

11/01/01 22:48:42 local Partially collapsed tilefish burrow complex with Cancer sp. crab

Photo: USGS

KL4 #4 OC02-12 10/28/02 ~193 m

Tilefish burrow complex in clay with sunken Sargassum thallus

Photo: USGS

20 cm

KL4 #20 OC02-12 10/28/02 ~193 m

Tilefish burrow complex in clay

Photo: USGS

IJ0 #12 OC02-12 10/29/02 ~116 m

Unidentified fish and galatheid crabs in tilefish burrow complex in muddy sand

Photo: USGS

IJ0 #25 OC02-12 10/29/02 ~115 m

Tilefish burrow complex in muddy sand with Astropecten americanus

Photo: USGS

WX7 #24 DE04-12 8/27/04 20:12:25 UTC 39º 28.6447’ N, 72 º 21.7587’ W 134.3 m

Tilefish burrow complex in clay

Photo: USGS20 cm

Tilefish burrow complex in clay with galatheid crab

Photo: USGS

20 cm

WX7 #30 DE04-12 8/27/04 20:16:59 UTC 39º 28.6521’ N, 72 º 21.8165’ W 134.4 m

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?

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.

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).

NEBO Hudson Canyon Tilefish Habitat NEBO Hudson Canyon Tilefish Habitat Investigation ObjectivesInvestigation Objectives

Rationale for use of HabcamRationale for use of Habcam1. 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.