Ageing of juvenile coral grouper (Plectropomus maculatus) reveals year-round spawning and recruitment: implications for seasonal closures.

Temporal patterns in spawning and juvenile recruitment can have major effects on population size and the demographic structure of coral reef fishes. For harvested species, these patterns are crucial in determining stock size and optimizing management strategies such as seasonal closures. For the commercially important coral grouper (Plectropomus spp.) on the Great Barrier Reef, histological studies indicate peak spawning around the summer new moons. Here we examine the timing of spawning activity for P. maculatus in the southern Great Barrier Reef by deriving age in days for 761 juvenile fish collected between 2007 and 2022, and back-calculating settlement and spawning dates. Age-length relationships were used to estimate spawning and settlement times for a further 1002 juveniles collected over this period. Unexpectedly, our findings indicate year-round spawning activity generates distinct recruitment cohorts that span several weeks to months. Peak spawning varied between years with no clear association with environmental cues, and little to no alignment with existing seasonal fisheries closures around the new moon. Given the variability and uncertainty in peak spawning times, this fishery may benefit from additional and longer seasonal closures, or alternative fisheries management strategies, to maximize the recruitment contribution from periods of greatest reproductive success.

A retrospective comparative study of open and endoscopic saphenous vein harvesting.

PURPOSE: To compare the operative variables, complications, and potential benefits of endoscopic saphenous vein harvesting (ESVH) with traditional open vein retrieval for coronary artery bypass grafting (CABG). METHODS: Data were collected retrospectively on 212 consecutive CABG patients from whom saphenous veins were harvested by one surgeon using either an open saphenous vein harvesting (OSVH) technique (n = 135) or ESVH (n = 77) performed with the ENDO-SAPH Vein Harvest System. Fifty-three patients underwent a purely endoscopic procedure, whereas 24 patients had either a combined endo-open procedure (n = 13) or were converted to an open technique (n = 11) because of equipment failure or adverse anatomical characteristics. Harvest time was measured from initial leg incision to aortic cross-clamping. Leg wound complications were evaluated on the basis of progressive severity. RESULTS: Harvest and procedural times were longer for the ESVH group (111 and 313 minutes, respectively) than for the OSVH patients (63 and 252 minutes, respectively, p < 0.001). Mean length of stay was not appreciably different: 11.7+/-6.2 days (range 3-52) for the OSVH group, compared with 11.0+/-6.0 days (range 3-41) for the ESVH patients (p = 0.40). Fewer complications occurred in the ESVH group when a purely endoscopic procedure was performed (17% versus 35% for OSVH, p = 0.012). Infection occurred in 1 OSVH and in 4 ESVH patients, but 3 of the endoscopic patients had a combined procedure. Bivariate correlational analysis showed that an increased number of incisions (r = 0.29, p < 0.01), obesity (r = 0.18, p < 0.01), and short stature (r = -0.16, p < 0.05) were associated with leg wound complications, but hierarchial stepwise regression analysis determined only short stature to be a predictive variable (beta = 0.17, R2 = 0.03). CONCLUSIONS: Despite increased operating time, ESVH results in fewer complications when a purely endoscopic procedure is performed.