The Graveyard seamount complex on the northern flanks of the Chatham Rise has several seamounts that have been managed as part of the seamount closures in 2001. The depths at which these seamounts exist are: 750-1250 m for peaks, and 1050-1600 m for seamount base.

As part of this management, a directed survey was undertaken to map the distribution of fauna between seamounts with various levels of fishing effort. Images taken using NIWAs Deep Towed Imaging System (DTIS) provided the main data source.

Surveys have been conducted on 3 occasions to collect image data of the benthic fauna/habitats to monitor changes over time:

• seamounts open to fishing;

• two unfished seamounts, now closed; and

• one previously fished, now closed.

This "natural experimental area" allows an evaluation of whether impacted habitat can recover over time following cessation of fishing, and the form the recovery may take.

Measured variables: benthic mega epifauna

Epibenthic sled: cod-end mesh size 25mm.

Year of sampling: seafloor imagery with seamounts camera in 2001; NIWAs Deep Towed Image System (DTIS) in 2006 and 2009.

Sampling frequency: 4 seamounts were sampled each survey, with up to 7 in 2006. The following seamounts were sampled each survey: Graveyard, Morgue, Gothic, and Diabolical.

Temporal resolution of individual samples: continuous video, still images every 1 minute (2001), 30 secs (2006), 15 secs (2009).

Sampling locations: at least 4 complete video transects on each seamount, with up to 8 transects on Morgue. Each transect was from the summit to the base of the seamount. Repear transects were made.

Number of records: 2001 survey, 220 images; 2006 survey, 5097 images; 2009 survey, 8164 images. Still images generally showed 6-8 sq.m of seafloor.

Other sampling method: epibenthic sled

Positional accuracy: depth, latitude,and longitude are measured by a device (HPR) attached to the camera system deployed from NIWAs research vessel Tangaroa.

Minimum size recorded: smallest megafauna 2-3 cm.

Sampling protocols and quality assurance was imposed on the methods. There were checks between recorders and one person examined all the images.

Data analysis: ongoing for a full comparison of the three surveys. Completed reports describing the surveys are listed above.