(location: top of Buitenratel) but were destroyed by boat traffic. Mussel growth
results were, however, promising.
In 2000, a more robust construction was developed for the zone D1 (zone of
0.09 km
2 , north of Noordpas, near buoy D1, extension of sandbank Smal bank,
13 km of the coast at Nieuwpoort) where boat traffic is not allowed. A first design
consisted of the floating frame with 45 mussel ropes of 10 m whose ends were
attached at one point. A weight prevented the ropes of friction against each other
and to get entangled (Fig. 2.4c–d). The whole construction was anchored with a
heavy weight and foreseen of a contra-weight to compensate for the tugging. Later,
it was decided to include a closed frame so the whole construction could be lifted at
once into the boat. By the end of 2000, however, the cages were lost due to
insufficient anchoring and floating devices.
In 2001, two different systems were designed for mussel seed collection and
grow-out. To capture mussel seeds, a longline of 200 m with floats was anchored
by means of two anchors of 1 t at each side, in the zone D1. A total of 20
polypropylene ropes of 5 m length and 12 mm thickness were attached to the
longline (Fig. 2.4b). The grow-out system consisted of floating cages with socks
hung inside (Fig. 2.4e). Despite the prohibition for boats to enter the D1 zone (quite
shallow), more than half of the longlines were destroyed and the grow-out cages
dislodged by boat traffic. Mussels grew very well on the sunken cages, reaching a
size of 6–7 cm in 10 months, despite the high densities. From 2002 to 2006, José
Reynaert continued his endeavor with private money and with scientific support
Fig. 2.4 (a–e): a construction of a mussel hang culture (used in 5b project 1998); b construction
for spat collection (used by José Reynaert in 2001); c–d Hang culture system with and without
closed frame (used in Pesca-Project 2000) e construction for grow-out. Graphics: Delbare (2001)
2 Offshore and Multi-Use Aquaculture with Extractive Species…
39
results were, however, promising.
In 2000, a more robust construction was developed for the zone D1 (zone of
0.09 km
2 , north of Noordpas, near buoy D1, extension of sandbank Smal bank,
13 km of the coast at Nieuwpoort) where boat traffic is not allowed. A first design
consisted of the floating frame with 45 mussel ropes of 10 m whose ends were
attached at one point. A weight prevented the ropes of friction against each other
and to get entangled (Fig. 2.4c–d). The whole construction was anchored with a
heavy weight and foreseen of a contra-weight to compensate for the tugging. Later,
it was decided to include a closed frame so the whole construction could be lifted at
once into the boat. By the end of 2000, however, the cages were lost due to
insufficient anchoring and floating devices.
In 2001, two different systems were designed for mussel seed collection and
grow-out. To capture mussel seeds, a longline of 200 m with floats was anchored
by means of two anchors of 1 t at each side, in the zone D1. A total of 20
polypropylene ropes of 5 m length and 12 mm thickness were attached to the
longline (Fig. 2.4b). The grow-out system consisted of floating cages with socks
hung inside (Fig. 2.4e). Despite the prohibition for boats to enter the D1 zone (quite
shallow), more than half of the longlines were destroyed and the grow-out cages
dislodged by boat traffic. Mussels grew very well on the sunken cages, reaching a
size of 6–7 cm in 10 months, despite the high densities. From 2002 to 2006, José
Reynaert continued his endeavor with private money and with scientific support
Fig. 2.4 (a–e): a construction of a mussel hang culture (used in 5b project 1998); b construction
for spat collection (used by José Reynaert in 2001); c–d Hang culture system with and without
closed frame (used in Pesca-Project 2000) e construction for grow-out. Graphics: Delbare (2001)
2 Offshore and Multi-Use Aquaculture with Extractive Species…
39