Abundance spectra for octocoral communities at the four sites within Coiba National Park, Panama. Black: base line, community at time 1; grey: community after 17 months population decline; white: community after 17 months recovery process from a punctuated anthropogenic disturbance. Cr, Carijoa riisei ; Het, Heterogorgia sp.; La, Leptogorgia alba ; Lc, Leptogorgia cofrini ; Lt, Leptogorgia taboguilla ; Lp, Leptogorgia pumilla ; Lr, Leptogorgia rigida ; Ma, Muricea austera ; Pc, Pacifigorgia cairnsi ; Pr, Pacifigorgia rubicunda ; Pi, Pacifigorgia irene ; Psm, Psamogorgia arbuscula ; Pe, Pacifigorgia eximia ; Pf, Pacifigorgia firma ; Ste, Pacifigorgia stenobrochis . 

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... than in reference monitored plots. At Frijoles, no recovery occurred in the disturbed plots (Figure 1). Visual inspection of the R ́nyi diversity profiles revealed differences in diversity between sites. Roca Hacha, Catedrales, and Jicarita demonstrated higher species richness and lower dominance compared to Frijoles, where species richness was lower and dominance was higher (Figure 2). Although an important population decline occurred at all sites, there was no notable change in the diversity profiles (i.e. overlapping black lines in Figure 2). The diversity profiles for recovering disturbed plots changed differently from site to site (Figure 2). Recovery at Roca Hacha occurred by increasing species richness and evenness simultaneously, while never reaching the diversity profiles of monitored reference plots. In contrast, the recovery at Catedrales moved from low richness and high evenness at sampling period 2 to high richness and low evenness at sampling period 5; thus the similarity of its diversity profile to that of the monitored reference plots increased over time. At Jicarita, species richness showed a relatively small increase whereas species evenness decreased over time. The data from Frijoles suggest that a small recovery took place after sampling period 4, as it showed a species evenness and lower species richness similar to data from the monitored reference plots. Community structure at each site during each sampling period was compared using five different theoretical models: broken-stick (null hypothesis), pre-emption, log-normal, Zipf, and Zipf–Mandelbrot (Table 3). In the baseline community at sampling time 1, community structure at Catedrales, Jicarita, and Roca Hacha best fit the pre-emption model (Akaike’s information criteria (AICs) 1⁄4 64.9, 58.0, 84.4, respectively) and community structure at Frijoles best fit the Zipf model (AIC 1⁄4 24.5). The best-fit model did not change after the population decline at Catedrales, Roca Hacha, and Frijoles, but it did change for Jicarita, where it shifted from the pre-emption to the log-normal model (AICs 1⁄4 58.0 and 54.3, respectively). The best-fit model changed to the null model after the disturbance at Catedrales, representing the broken-stick theory (AIC 1⁄4 31.51). At Jicarita, the Zipf model had the lowest AIC value (AIC 1⁄4 23.84); however, the AIC value for the pre-emption model (24.47) was only slightly higher, and this was the one that best fit the baseline community. At Roca Hacha, the best-fit model did not change over the 17 month recovery process, implying that the community was similarly structured after disturbance. This analysis was not performed for disturbed plots at Frijoles due to the low population size (eight colonies). The extent of the similarity in community structure between a reference baseline community and a community after population decline and recovery was analysed using the Bray – Curtis similarity matrix, tested with an ANOSIM, and plotted as a cluster figure. No significant dissimilarity in community structure was found between the baseline community and the community after the 17 month population decline at any of the study sites (Table 4). Jicarita had the lowest similarity after the population decline, at less than 80% (Figure 3). The least similarity was found in comparisons between disturbed and undisturbed plots. Community composition was only significantly different, however, at Jicarita (Table 5; Figure 4). The RAD plot for Frijoles suggested no recovery, with a substantial difference in community composition between disturbed and reference plots; however, the ANOSIM for this site showed the opposite pattern, with a non-significant difference between disturbed and reference plots (Table 5; Figure 4). Abundance spectra were plotted to determine if species turnover occurred during the population decline or the recovery of disturbed plots. These spectra showed a similar species- specific composition after the population decline and, to a lesser extent, after the disturbance at Catedrales, Roca Hacha, and Frijoles. Leptogorgia alba was the most common species found at these three sites. This species did not lose its hierarchical rank after the population decline or after disturbance at Catedrales or Frijoles, and it became the second ranked species at Roca Hacha, where Pacifigorgia rubicunda became the first. At Catedrales, intermediate species changed in rank after disturbance and there was a significant increase of one rare species ( Leptogorgia rigida ). After the population decline in Jicarita, the more abundant species, P. rubicunda , further increased in abundance while the intermediate species, C. riisei became absent. Jicarita experienced species reorganization after disturbance. There, the most common species originally was P. rubicunda , which became rare after the disturbance. Leptogorgia cofrini , which was originally third in rank, became the first and dominant species after the disturbance (Figure 5). This reorganization of species abundance at Jicarita was identified but not described by the ANOSIM and cluster analysis. The baseline data from Catedrales, Jicarita, and Roca Hacha best fit the niche pre-emption model. This model describes low species evenness, as usually seen in communities that are highly dominated by few species, in resource poor environments, after an environmental disturbance, or in recently colonized environments (Giller, 1987; Fattorini, 2005). The RAD graphs and the R ́nyi plots showed a non-significant change in community composition at three of the sites, Roca Hacha, Catedrales, and Frijoles, after the population decline, and this result was confirmed by the ANOSIM and cluster analysis. There was no species turnover, as can be seen in the abundance spectrum. At Jicarita, the best-fit model switched from the pre-emption to the log-normal model, nonetheless, the log-normal model is related to the pre-emption model but with a greater number of rare species (Fattorini, 2005). This change was also indicated by the low similarity in the cluster analysis between sampling periods 1 and 5 relative to the other sites. Analysing the effect of the disturbance on species diversity, abundance, and community composition was more complex. Disturbed plots did not regain the total number of species present in monitored reference plots. As predicted by Mac Nally (2007), rare species were lost in a greater proportion than common species, which also decreased in abundance. The octocoral community at Frijoles had the lowest initial population size and the highest population decline, which could be a factor that affected the recovery in cleaned plots shown by the RAD graphs. When the community structure of Frijoles was analysed with the ANOSIM, however, there was not a significant difference between disturbed and undisturbed plots, and this was reflected in the cluster graph. As in the other study sites, treated plots at Frijoles still had some species missing after the 17 month recovery process. The absence of these species had a larger effect on community recovery at Frijoles. One possible explanation is that initially there was low species richness and abundance and strong dominance by L. alba in both disturbed and undisturbed plots. In this case, the RAD was more sensitive to rare species than the ANOSIM permutation test, which gives more weight to the presence and hierarchy of the dominant species. This effect became clear in the abundance spectrum; the same dominant species was equally present in disturbed and undisturbed plots. In the case of Frijoles, the R ́nyi plot was a good community descriptor because it predicted the change in species richness and the non-significant change in species evenness after disturbance. The RAD pattern of recovering plots at Jicarita did not change between sampling periods 3 and 5. This pattern did not resemble the pattern from reference plots, indicating that the community was assembling differently, with less species richness and less evenness, as reflected in the R ́nyi entropy plot. The difference in community structure after disturbance was confirmed by the ANOSIM. The reason for this significant difference was evident in the abundance spectrum, which showed that Jicarita recovered with a different species composition: a non-dominant species ( L. cofrini ) became dominant after the disturbance and a previously common species ( P. rubicunda ) became rare. Jicarita was the site with the lowest similarity between the initial community and the community after the population decline (Figure 3), and it was the only site for which the best-fit model changed when comparing the effect of both population decline and disturbance. The fact that the similarity was lower after the population decline could indicate that the community structure at Jicarita is more vulnerable to disturbance than that of the communities found at the other study sites. The RADs and R ́nyi plots showed that there was a change in the community structure at Jicarita, and the ANOSIM confirmed the extent of this change. Although the ANOSIM did not show a significant difference between disturbed and monitored reference plots at Roca Hacha and Catedrales, meaning that the original community structure was recovered in the disturbed plots, the RAD, R ́nyi, and cluster plots reveal some interesting trends. Simple visual inspection of the RAD and R ́nyi plots shows that Catedrales had a better recovery process than Roca Hacha. However, the opposite trend was shown in the cluster analysis and by the best-fit model. Cluster analysis showed a higher similarity between disturbed and undisturbed plots at Roca Hacha ( . 80%) than at Catedrales (60%). In the same way, Roca Hacha fit the pre-emption model before and after the disturbance, as opposed to Catedrales, in which recovered disturbed plots fit the null hypothesis of the broken- stick model and the base line mature community best fit ...