TOPS Oysters Consulting Ltd

63 Todds Bush Rd, RD1
Nelson 7071, New Zealand

New oyster growing system

The TOPS Oysters™ technology concept is based on growing oysters as naturally as possible without the need for massive structures or systems to contain the oysters. TOPS Oysters™ believes that this makes it one of the most animal and environmentally friendly growing systems around.

With TOPS Oysters™, the initial emphasis is on growing quality spat. Investment in a good oyster "childhood" pays off even more so with TOPS Oysters™, because from spat stage until harvest, there is no more product handling needed. No more grading, biomass adjustment, or fouling control measures are involved. Thanks to the optimal spacing provided by TOPS Oysters™ at the point of seeding, no more husbandry intervention is needed until harvest. And there is even  mechanization of the seeding process possible.

TOPS quality spat seeding 25-30mm long
Well spaced oysters, free hanging
TOPS oysters ready for harvest 8-12 months from seeing

Free, non-caged growing

Like wild-grown oysters, TOPS Oysters™ are reared without any enclosures, providing free, unhindered water exchange and food supply. This environment mimics the best growing conditions that nature can provide for a quality oyster.

TOPS intertidal oysters on horizontal frame
TOPS submerged longline oysters

Optimum spacing

Different from any wild oyster, the well-prepared and selected TOPS Oysters™ are grown from spat onwards above the bottom sediment, suspended on structures under perfect conditions with optimum spacing to avoid crowding and competition. Growing oysters under these conditions without the stress of crowding makes the difference!  TOPS Oysters™ show a perfect balance of growth between shell and meat.

Evenly spaced oysters - TOPS growing system
5 five months old subtidal oysters grown with TOPS
TOPS grown oyster 10 months old

No handling after seeding

By starting grow-out under the best conditions provided by hardened well-selected uniform spat, no more intervention in terms of handling is needed until harvest. Perfect spacing eliminates crowding so the oysters can grow unhindered to reach optimum quality. With TOPS Oysters™ uniform market size quality oysters can be obtained.

Uniformly grown TOPS oysters

Mechanized seeding

Seeding involves the gluing of spat onto tags/labels which are attached to tape at the desired spacing. This process can benefit from mechanization, using a seeding machine with the capacity to glue up to 25,000 oysters per day with two staff. This capacity is adequate for commercial production and can easily be expanded if required. 

TOPS Gluing oyster spat on tape
TOPS freshly seeded oyster spat on tag/tape

During mechanized seeding, TOPS Oysters™ spat can be attached to the tag in random direction. With the feature of the “loose” attachment of the spat and tag to the tape, oysters can freely rotate around the axis of the pin, and self-orientate.

So irrespective of their original direction at the time of gluing, the oysters will all end up pointing in the same direction during grow-out. This is an important feature of TOPS Oysters™ resulting in efficiently spaced oysters that self-orientate without touching each other.

TOPS Oyster seeding machine
Oyster growing, spacing on line


Harvesting of TOPS Oysters™ can be efficiently carried out in a number of ways, both manually or mechanized.  The method depends on the type of structure that the grower has used to suspend the seeded tape from. Common methods include suspension of tape from longlines, frames, racks, or stakes.

Harvesting involves the cutting off of a small pin that attaches the tag (label) and oyster to the tape. The tag is left attached to the oyster to form the label.

Oyster harvesting platform
TOPS grown oyster harvesting

Harvested TOPS Oysters
tops grown oyster harvesting