270 
Fishery Bulletin 95(2), 1 997 
taries was based upon results from earlier releases 
(Leber, 1995; Leber and Arce, 1996; Leber et al. 1 ) where 
release habitat appeared to be critical to survival. 
All releases were conducted at about noon or early 
afternoon. The successive weekly release lots 
spanned the rising tide (lot 1 on a low tide; lot 2 on a 
rising tide; lot 3 on a low tide in both seasons). 
Releases were made near the shoreline in water from 
0.5 to 1.5 m deep. There was a wider range of salini- 
ties at the southernmost site (Kaneohe Stream; 
Table 2). 
Monitoring 
Beginning 21 May 1991, we monitored abundances 
of hatchery-released and wild Mugil cephalus in 
Kaneohe Bay monthly for 11 months by sampling 
with cast nets. Recaptured tagged fish were removed 
from collections and returned to the laboratory for 
tag analysis. The first field collection after spring 
and summer releases began 2 weeks after the middle 
release lot (lot 2) was planted. 
Each monthly collection was conducted over ap- 
proximately a 2-week period. Collections were made 
at six nursery sites (sampling stations) within 
Kaneohe Bay. Collections were made for about an 8- 
hr period during the day at each sampling station. 
Stations were established in the vicinity of docu- 
mented striped mullet nursery habitats at various 
tributaries located throughout the bay (Leber, 1995; 
six streams in Fig. 1: Waiahole, Kaalaea, Kahaluu, 
Heeia, Keaahala, and Kaneohe Streams). 
To standardize collection effort, at each station two 
substations were sampled — one substation was es- 
tablished upstream, the other near the mouth of the 
tributary. Within substations, 15 cast net throws 
were made. To broaden the range of microhabitats 
and fish size-ranges sampled, two sizes of cast nets 
were employed. Ten of the 15 casts per substation were 
made with a 5-m diameter, 10-mm mesh net, and 5 
casts were made with a 3-m diameter, 6-mm mesh net. 
Thus, a total of 180 casts were made each month. 
Placement of net samples was stratified over ob- 
served schools of striped mullet juveniles. Completely 
random sampling in preliminary collections yielded few 
wild striped mullet and very few tagged individuals. 
Striped mullet schooled in fairly low densities within 
these clear-water nursery habitats, and our stratified- 
random collections targeted those schools. Neverthe- 
less, the sample data used to determine proportions of 
tagged versus untagged mullet were randomly distrib- 
uted because we had no a-priori indication that schools, 
once sighted, contained tagged individuals. 
All striped mullet sampled were measured and 
checked for tag presence with a field-sampling de- 
tector (Northwest Marine Technology, Inc., Shaw Is- 
land, WA). Tagged fish were placed on ice and re- 
turned to the laboratory where the tags were recov- 
ered, and each fish was weighed and measured. 
Untagged fish were held at the field site in oxygen- 
ated water and then released after the 30 cast-net 
samples were completed. 
Treatment identifications were made on the basis of 
the tags retrieved from recaptured fish. In the labora- 
Tafofe 2 
Physical data recorded at the two release sites in Kaneohe Bay, Kahaluu Stream and Kaneohe Stream, for each release lot 
(release date) of striped mullet, Mugil cephalus. IN = incoming. 
Season Temperature (°C) Salinity ( %c ) 
and release 
site (stream) 
Release 
date 
Tide 
stage 
Secchi 
(cm) 
Depth 
(cm) 
Top 
Bottom 
Top 
Bottom 
Spring 
Kahaluu 
5/03/91 
IN 0.2' 
51 
59 
33 
32 
11 
12 
Kaneohe 
5/03/91 
IN 0.5' 
110 
120 
27 
27 
6 
32 
Kahaluu 
5/10/91 
IN 0.8' 
70 
75 
29 
26.5 
15 
27 
Kaneohe 
5/10/91 
IN 1.6' 
92 
92 
26 
27 
4 
35 
Kahaluu 
5/17/91 
IN 0.0' 
25 
40 
29 
29 
24 
26 
Kaneohe 
5/17/91 
IN 0.0' 
55 
80 
28 
28.2 
3 
15 
Summer 
Kahaluu 
7/12/91 
IN 0.8' 
57 
57 
27.5 
28 
11 
28 
Kaneohe 
7/12/91 
IN 0.8' 
75 
122 
27 
27 
11 
35 
Kahaluu 
7/19/91 
IN 1.6' 
85 
100 
25.3 
27 
10 
19 
Kaneohe 
7/19/91 
IN 1.7' 
115 
115 
26 
27 
4 
35 
Kahaluu 
7/26/91 
IN 0.7' 
40 
70 
27.6 
28 
12 
20 
Kaneohe 
7/26/91 
IN 0.9' 
65 
90 
26.2 
26.5 
6 
34 
