The MacKinnon Lists Technique: An efficient new method for rapidly assessing biodiversity and species abundance ranks in the marine environment

variables as significant effects compared to the MaxN methodology as sampling effort was reduced. Due to the greater use of data available in video surveys, the MLT appeared to pro- duce more stable estimations of species richness, suggesting that reliable assessments of biodi- verse communities could be achieved with lower sampling effort. These results suggest MLT is a viable method to assess spatial or temporal changes in spe- cies richness, relative abundance and community composition in marine environments and therefore could be a valuable tool for rapid conservation assessments in marine environments and possibly more widely under other circumstances where resources for sampling are limiting. The consistency of both methods in generating similar ranks of the most abundant species and in generating comparable patterns of relative abundance for species of key conservation concern suggest that MLT should be a useful tool to assess the relative abundance of target spe- cies. This is encouraging not only for surveys in the marine environment, but also more gener- ally, as previous tests on highly diverse tropical avian communities have often struggled to collect sufficient data from multiple methods to compare relative abundance ranks of more than a few species [35,37]. The choice of sampling technique and method of analysis for biodiversity assessments in general often depends on the researcher’s experience and preference, budget, study aim, focal species and a choice between different biases associated with different techniques [12]. Fjeldsa

(1999) advocates the use of MLT for birds as being a highly time-efficient method as lists sam- ples can be continuously generated while randomly moving through a habitat. This is a poten- tially significant advantage of the MLT compared to other methods traditionally used in avian studies, such as point counts where the time moving between survey points can significantly reduce data collection time [37]. In the context of field surveys whether in terrestrial or marine environments, MLT could allow a surveyor to cover a greater survey area in less time, generating a greater number of samples and often will require almost no prior preparation time for laying out survey grids or Table 5. Comparison of ability of MaxN and MTL methods to detect significant effects on community composition. PERMANOVA results of square root trans- formed relative abundance data generated by MaxN and MLT using Bray Curtis dissimilarity matrix and one dummy variable. Significant values are highlighted bold. Source Df MS Pseudo-F P(perm) MaxN Status 1 6528.5 4.1 0.007 Depth 1 8623.2 5.3 <0.001 StatusxDepth 1 3424.4 2.1 0.051 Site(Status) 8 1507.9 0.8 0.810 DepthxSite(Status)�� 7 1576.5 0.8 0.760 Residual 9 1902.8 Total 27 MLT Source Df MS Pseudo-F P(perm) Status 1 7373.4 2.4 0.007 Depth 1 9207.4 3.2 0.002 StatusxDepth 1 4484.1 1.6 0.100 Site(Status) 8 3070.2 1.0 0.610 Video(Site(Status)xDepth) 17 3296.2 1.3 0.006 Res 98 2604.1 Total 134 https://doi.org/10.1371/journal.pone.0231820.t005 PLOS ONE A new method for monitoring marine biodiversity

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