Evaluation of the Use of Autonomous Reef Monitoring Structures (ARMS) for Describing the Species Diversity of Two Coral Reefs in the Yucatan Peninsula, Mexico

Autonomous reef monitoring structures (ARMS) have been proposed as a standardized, passive, nondestructive sampling tool. This study assessed the ability of ARMS to capture the cryptic species diversity of two coral reefs by recording species richness and taxonomic representativeness using conventional taxonomy. The capacity of ARMS, as artificial substrates, to favor the establishment of nonindigenous species over native species was also evaluated. The use of ARMS allowed the detection of 370 species morphotypes from nine phyla, yielding 13 new records of geographic distribution expansion, one exotic species for the Gulf of México and the Caribbean Sea, and six newly described species. It was also possible to make spatial comparisons of species richness between both reefs. ARMS captured cryptic diversity exceptionally well, with the exception of echinoderms. Furthermore, these artificial structures did not hinder the colonization ability of native species; in fact, the colonization patterns on the structures themselves represented the spatial differences in the structure of benthic assemblages. This study represents the first effort to make a conventional taxonomic description of the cryptic fauna of the Yucatan Peninsula using ARMS. It is recommended to assess coral reef species diversity, but more taxonomists specialized in marine invertebrates are needed.

Resident Perceptions of Ecosystem Services Provided by U.S. Coral Reefs: Highlights from the First Cycle of the National Coral Reef Monitoring Program’s Socioeconomic Survey

Despite being among the most valuable ecosystems on Earth, coral reefs face ongoing threats that could negatively impact the human populations who depend on them. The National Coral Reef Monitoring Program (NCRMP) collects and monitors data on various aspects of U.S. coral reefs to provide a holistic understanding of the status of the reefs and adjacent human communities. This paper explores results from the NCRMP’s first socioeconomic monitoring cycle using an ecosystem services framework and examines how these results can be used to improve coral reef management in the following U.S. coral reef jurisdictions: American Samoa, the Commonwealth of the Northern Mariana Islands, Florida, Guam, Hawai’i, Puerto Rico, and the U.S. Virgin Islands. Results suggest that residents in the U.S. Pacific coral reef basin may hold stronger cultural and provisioning values, whereas residents in the U.S. Atlantic coral reef basin may hold stronger regulating values. These findings suggest that outreach efforts have been successful in communicating benefits provided by coral reef ecosystems to the public. They also provide insight into which ecosystem services are valued in each jurisdiction, allowing resource managers to make science-based decisions about how to communicate conservation and management initiatives.

Comparing Coral Colony Surveys From In-Water Observations and Structure-From-Motion Imagery Shows Low Methodological Bias

As the threats to coral reefs mount, scientists and managers are looking for innovative ways to increase the scope, scale, and efficiency of coral reef monitoring. Monitoring changes in coral communities and demographic features provides key information about ecosystem function and resilience of reefs. While most monitoring programs continue to rely on in-water visual survey methods, scientists are exploring 3D imaging technologies such as photogrammetry, also known as Structure-from-Motion (SfM), to enhance precision of monitoring, increase logistical efficiency in the field, and generate a permanent record of the reef. Here, we quantitatively compare data generated from in-water surveys to SfM-derived metrics for assessing coral demography, bleaching, and diversity in the main Hawaiian Islands as part of NOAA’s National Coral Reef Monitoring Program. Our objectives were to compare between-method error to within-method error, test for bias between methods, and identify strengths and weaknesses of both methods. Colony density, average colony diameter, average partial mortality, prevalence of bleaching, species richness, and species diversity were recorded using both methods within the same survey areas. For all metrics, the magnitude of between-method error was comparable to the within-method error for the in-water method and between method error was significantly higher than within-method error for SfM for one of the seven metrics. Our results also reveal that a majority of the metrics do not vary significantly between methods, nor did we observe a significant interaction between method and habitat type or method and depth. Exceptions include estimates of partial mortality, bleaching prevalence, and Porites juvenile density–though differences between methods are generally small. Our study also highlights that SfM offers a unique opportunity to more rigorously quantify and mitigate inter-observer error by providing observers unlimited “bottom time” and the opportunity to work together to resolve difficult annotations. However, the necessary investment in equipment and expertise does present substantial up-front costs, and the time associated with curating imagery, photogrammetric modeling, and manual image annotation can reduce the timeliness of data reporting. SfM provides a powerful tool to reimagine how we study and manage coral reefs, and this study provides the first quantified methodological comparison to validate the transition from standard in-water methods to SfM survey methods for estimates of coral colony-level surveys.

First record of two sublittoral amphipods from Hawai‘i

The first record of two genera of sublittoral amphipods, Autonoe Bruzelius, 1859 and Perioculodes G.O. Sars, 1892, is provided for Hawai‘i. The specimens most closely match Autonoe seurati (Chevreux 1907) and Perioculodes aequimanus (Kossmann, 1880). They were collected from an autonomous reef monitoring structure deployed in Honolulu Harbor, O‘ahu. Both species are likely recent introductions.

Artificial Reef Monitoring Structures (ARMS) providing insights on hard substrate biodiversity and community structure of the Eastern Mediterranean Sea

Monitoring marine biodiversity in hard-bottom habitats is challenging as it typically involves resource-intensive, non-standardized, and often destructive sampling methods that limit its scalability. Differences in monitoring approaches furthermore hinder inter-comparison among monitoring programs. Standardised collectors such as Artificial Reef Monitoring Structures (ARMS) can be used to monitor status and changes of hard substrate communities in coastal environments. In addition, ARMS constitute an early-warning system for marine biological invasions by identifying newly introduced Non-Indigenous Species (NIS) and track the migration patterns of already known NIS in European continental waters. In the framework of ASSEMBLE+ project and as part of the European ARMS programme (ARMS-MBON) (Obst et al. 2020), ARMS were deployed in two locations in Greece and, more specifically, in the marina of the Old Venetian Harbour of Heraklion (1HERP) and in the Underwater Biotechnological Park of the Hellenic Centre for Marine Research (2UBPC). The ARMS deployment and retrieval dates are shown in Table 1; deployment and retrieval were done according to the standards and protocols established by the Smithsonian Institution. Upon retrieval, the plates from the ARMS were disassembled, photographed (Fig. 1a) and samples of both the motile and sessile communities were collected for molecular analysis. Each sampling event produced three fractions (sessile, motile 90–500 μm and motile 500 μm−2 mm) as well as a stack of plate and specimen images. DNA was extracted from the sampled fractions and amplified by PCR, targeting different molecular markers (18S rRNA, COI and ITS). Resulting amplicons were sequenced using Illumina MiSeq Reagent Kit v3 (2 × 300 bp) and analyzed using PEMA (Zafeiropoulos et al. 2020). All raw sequence files of this study were submitted to the European Nucleotide Archive (ENA) (Harrison et al. 2021) with the study accession number PRJEB33796. Images were analyzed using photoQuad image processing software (Trygonis and Sini 2012), which is specialised for the analysis of sessile biodiversity on photoquadrats. Cover of sessile taxa was measured by superimposing on every image 100 randomly distributed points. Each point was manually assigned to the corresponding taxon or morpho-functional category based on external morphological characters. Repeatable workflow procedures for integrated processing of image and sequence data are currently under development as part of the LifeWatch-ERIC Internal Joint Initiative on NIS. In addition, all ARMS-related data are stored in the ASSEMBLE Plus data collection of the Marine Data Archive (MDA) using a Darwin Core Archive (DwC-A) format, including the linkages to the images and sequences (Exter et al. 2020). Comparison of traditional biodiversity assessment methods, such as image-based identifications, complemented by the eDNA metabarcoding results, will shed light on the investigation of marine biodiversity patterns in the Eastern Mediterranean Sea (Fig. 1b). Furthermore, the results will provide crucial information on the importance of ARMS for biodiversity assessment and as an efficient tool to monitor community shifts and invasion events in marine ecosystems undegoing fast change.