Ministry for Primary Industries 'beach' database – intertidal shellfish

These surveys assess the status of the cockle and pipi populations in areas targeted by non-commercial fisheries at a number of sites in northern North Island, from the wider Auckland region to Northland, Waikato, and Bay of Plenty.The surveys determine the distribution, abundance and size frequency of pipis (Paphies australis), cockles (Austovenus stutchburyi) and tuatua (Paphies subtriangulata). The broad objective is to compare shellfish data on beaches closed to shellfish gathering and on beaches that may in future be candidates for closure and/or are subject to heavy collecting pressure in the Auckland Fisheries Management Area.

Of the beaches surveyed to date, Raglan harbour, Whangamata harbour, Tairua harbour, Whangapoua Harbour, Whitianga Harbour, Marakopa Estuary, Aotea Harbour and Waikawau (on the Firth of Thames coast) are within the Waikato Region. In 2016/17, three sites were surveyed in the Waikato Region - at Aotea, Whangamata and Whangapoua. Population estimates, standard errors and % Coefficient of Variance are given for cockles, pipi and tuatua (Papamoa only), with comparison over the last three years surveyed. Mean densities and length statistics are also provided. These data include the proportion of large individuals, defined as over 30 mm shell length for cockles and over 50 mm shell length for pipi. The data collection also includes the proportion of juveniles that are considered to be recruits, defined by shell lengths less than 15 mm for cockles and 20 mm for pipi.

Beaches in the Auckland Fisheries Management Area, including Waikato beaches - Raglan Harbour, Whangamata Harbour, Tairua Harbour, Waikawau (Firth of Thames), Aotea Harbour, Whangapoua Harbour.

Raglan Harbour – Whangamata Harbour – Tairua Harbour – Waikawau (Firth of Thames) – Whangapoua Harbour –

1993 - ongoing

Consultation with harvesters to gather information on the extent and distribution of the harvested beds within the harbours.Data from previous surveys used to model populations and draw preliminary conclusions about the most efficient allocation of sample units. Two stage random stratified sampling methodology (Francis, 1984). The first phase sampling programme was based on stratum defined by information on fishing areas gathered from the MPI staff, harvesters and historical surveys. The stage two sampling regime was determined using an optimization programme based on the information from the first phase data. Initially annual, less frequent more recently. Different sites are surveyed each year.

Survey sites were chosen to cover the known harvested areas, and not the complete harbour/beach area. Thus population estimates do not represent the entire population of pipi and cockles of the sampled harbours. There has been some modification to the methodologies previously used for Auckland intertidal beaches. Modifications were made where information from the 1999 survey showed that altering the location and / or size of the strata on a particular beach could make significant improvements Additional harbours/beaches have been added to the survey over time. Whangapoua Harbour has only been sampled in 2003. Not all beaches sampled every year.

report, electronic – stored as relational database 'beach'. Results reported - available online - see link below.

This data is used to identify where harvesting restrictions may be required to protect the fishery.

See Ministry of Primary Industries. Data report attached.

Ongoing