Increasing anthropogenic and (family Xeniidae), and sp. ratio of sclerite weight to tissue weight in polyps. As octocorals constitute an ecologically conspicuous benthic component on coral reefs (e.g., Benayahu and Loya 1981; Jeng et al. 2011), it is important to predict their response to a scenario of increased planulae, colonies were collected and transferred into aquaria with running seawater (Yacobovitch et al. 2003). The following morning released planulae were pipetted out and transferred to Petri dishes, with preconditioned microscope slides or water papers (2 weeks immersion on the reef) as settlement substrate, for 2C3 weeks. After the planulae had metamorphosed into primary polyps, they were transferred to the experimental pH system. The system consisted of three water tables with two pH treatments: pH 7.6 and 7.3 ((= 100 colonies), (15 adult and 70 primary polyps), and sp. (twenty-one 3 3 cm fragments), were equally divided among the two pH treatments (7.3 and 7.6) and the control (8.2). The colonies and primary polyps were placed in transparent 6 L PVC containers, supplied with an air stone (JUN ACO-5503, China Air pump; Guangdong Hailea Group Co., Ltd., Raoping County, Guangdong Province, China), and positioned under 400 W metal halide lamps, supplying 200 (AprilCMay 2009, FebruaryCMay 2010, and AugustCSeptember 2010; in the last one only pulsation was measured), one for (colonies: FebruaryCMay 2010, primary polyps: OctoberCNovember 2009), and one for sp. (JuneCOctober, 2008). After polyps were removed from the colonies of in order to determine the biological featuresthe colonies were returned to the IUI reef, whereas those of were repeatedly sampled. Primary polyps of and sp. fragments were sacrificed for the measurements. The octocorals were deliberately deprived of food. Biological assays In order to test the effect of the pH treatments on the biological Cannabiscetin cost features of the octocorals, experiments were conducted over a period of 30C90 days in Xeniidae and 5 months in sp. At different time points (see Results), samples comprised of six randomly selected polyps from each colony of (= 2C8 colonies), and a fragment from sp. (= 5C7 fragments), were placed in filtered seawater (FSW, 0.2 the remaining content of each sample was centrifuged again, 1 mL of cold acetone 90% (4C) was added to the pellet, and it was incubated at 4C for 18 h in the dark. Chlorophyll concentration was decided using spectrophotometry (Ultrospec 2100 pro; GE Bioscience, Piscataway, New Cannabiscetin cost Jersey), following Jeffrey and Humphrey (1975). An additional sample of six polyps of (tissue and sclerites) was dried overnight and then weighed using analytic balance (ViBRA AJ-320CE; Yushima, Bunkyo-ku, Tokyo, Japan; precision 10?3). Their sclerites were obtained by dissolving the tissue with 10% sodium hypochlorite, followed by repeated rinsing in double-distilled water (DDW), and then a wash with 95% alcohol (Aharonovich and Benayahu 2011). The alcohol was removed and the tubes were kept open overnight at room heat to dry. The sclerites of each sample were weighed and the ratio between sclerite weight to polyp weight SPTAN1 in was decided. The possible effect of decreased polyps was examined in colonies maintained in the experimental system, by means of three video recordings taken from five colonies (1 min each; Canon PowerShot G9 camera, Ohta-ku, Tokyo, Japan). Six polyps were randomly chosen from each video per colony and the number of pulses of the polyps per 1 min was counted and averaged (SD). In the reef, the pulsation of colonies was determined by underwater video Cannabiscetin cost recordings, using a Canon PowerShot G9 camera, Japan (December 2010, between 1000 and 1200 h). Each colony was photographed three times for 1 min (= 5 colonies), and the number of pulses of six randomly chosen polyps per 1 min was calculated. Statistical analysis Analysis of variance (ANOVA) was performed on the data using SPSS 15.0 (IBM Corporation, Armonk, New York) and STATISTICA 8 (StatSoft, Inc, Tulsa, Oklahoma). Log transformation was conducted on part of the data in order to achieve normal distribution (see Results). Results are expressed as mean standard deviation (SD). Results Throughout the experiments, little mortality was noted among the octocoral colonies and primary polyps, and they maintained.