17 Jul 2026

Application of GPS/GSM (Global System for Mobile Communications) Tag Technology to Investigate Seasonal Habitat Use by a Coastal Bird: A Pilot Study Using the Royal Tern (Thalasseus maximus)

Purpose: This technical note was developed by personnel from the US Army Engineer Research and Development Center–Environmental Laboratory (ERDC-EL) to describe the application of GPS/GSM (Global System for Mobile Communications) technology to wildlife studies to assess the effects of coastal engineering operations. GPS/GSM tags utilize cell tower transmissions to accurately locate animal positions in the landscape. While some satellite-based wildlife tags use Doppler technology, the GPS/GSM tags rely on GPS-based technology, which improves level position accuracy (e.g., ±30 m GPS/GSM tags versus ±300 m Doppler tags) in the landscape.* Doppler satellite tags break down distance accuracy into six location categories that range from ≤150 m to over 1,000 m, with a general average location accuracy of ≥300 m. The level of position accuracy with GPS/GSM tag technology permits researchers to determine if tagged birds are utilizing recently engineered coastal habitats (e.g., renourished beaches, dredged material islands, and restored wetlands), natural habitats, or minimally engineered coastal habitats. GPS/GSM tags could also be used to assess the frequency and seasonal changes of habitat use. Many coastal birds are known to breed on coastal dredged-material islands, often in response to coastal habitat loss wrought by dredging operations and other engineering actions (Soots and Landin 1978). In these same coastal areas, habitat degradation can occur through increased erosion and increased storm frequency and severity. The resulting habitat loss contributes to observed declines in coastal bird populations (Iglecia and Winn 2021; Newton 2004). These long-term population declines are not solely affecting coastal breeding species (Rosenberg et al. 2016). Habitat loss and population declines are also affecting many long-distance migrants that are seasonally transient and, thus, found along coastal habitats of the conterminous United States (Winn et al. 2013). The federally threatened Red Knot (Calidris canutus) is an example of a coastal transient species. Numerous other coastal birds currently experiencing population declines are potential candidates for future federal listing (Winn et al. 2013; Iglecia and Winn 2021). Interestingly, survey data suggested the Snowy Plover (Charadrius nivosus) avoids beaches that have been subjected to renourishment (Lott 2009; Lott and Fischer 2011), indicating that there may be variable, species-specific seasonal responses to coastal engineered habitats that remain poorly understood for many coastal birds. Therefore, there is a growing interest in determining the seasonal habitat needs of resident and migrant coastal birds and in approaches to beneficial uses of dredged material (BUDM) that could be used to design and construct year-round habitats (Guilfoyle et al. 2019, 2024).* However, much more research is required to determine the basic ecology, seasonal distribution, and seasonal habitat requirements of North American coastal birds to facilitate improved coastal habitat restoration and conservation. This technical note describes a pilot study in which 10 GPS/GSM tags were affixed to breeding Royal Terns (Thalasseus maximus; Figure 1) captured on South Island of the Hampton Roads Bridge-Tunnel in coastal Virginia. This study was part of a larger project to compile best management practices (Guilfoyle et al. 2019) and suggested management strategies† and was funded through the Ecosystem Management and Restoration Research Program (EMRRP). The Royal Tern was selected for this effort due to its relatively large size, which was suitable for a GPS/GSM tag, its known dependence on dredged-material islands for breeding, and its use of open beach habitats in the Southeastern United States and along the Gulf Coast during the wintering season.

4 Jun 2026

Brief Overview and Guide to Developing Monitoring and Adaptive Management Plans

Purpose: The purpose of this technical note is to summarizes key points on monitoring and adaptive management from the more detailed US Army Corps of Engineers (USACE) report ERDC/EL SR-19-9, “A Systems Approach to Ecosystem Adaptive Management: A USACE Technical Guide” and to provide a quick guide to developing monitoring and adaptive management plans (MAMPs) relevant to ecosystem restoration and mitigation projects. Although this report was written specifically for USACE projects, it is applicable to most restoration and mitigation projects. This guide does not supersede current or future USACE policy or guidance, nor is it applicable to private mitigation projects regulated by USACE.

11 Feb 2026

Oyster Reef Ecosystem Recovery Monitoring: A Habitat Case Study for the US Army Corps of Engineers Aquatic Restoration Monitoring for Ecosystem Recovery (ARMER) Network

Abstract: Oyster reefs are native to oceanic coasts of the contiguous United States, are great contributors to secondary production in estuaries, and provide food and other services to humans. Unfortunately, oyster reefs have become functionally extinct throughout much of their historical range due to overharvesting, disease, poor water quality, and weather-related drivers. Restoration efforts are underway in response to these population collapses and seek to replenish oyster populations to a level sustainable for ecosystem services. To evaluate effectiveness of these restoration interventions and characterize oyster reef recovery status on large scales, coordinated monitoring is needed to facilitate long-term collection, storage, and dissemination of data. The US Army Corps of Engineers has proposed the development of the Aquatic Restoration Monitoring for Ecosystem Recovery (ARMER) Network, a monitoring system composed of nationwide restoration and reference sites, to generate high-quality, replicated datasets to address large-scale ecosystem restoration challenges. This report details a framework of recovery attributes and associated monitoring metrics and methods proposed to characterize oyster reef habitat recovery following ecosystem restoration interventions. Monitoring recommendations, as well as existing monitoring networks and communities of practice, are discussed as key potential facets and partners in the operationalization of ARMER.

8 Sep 2025

US Army Corps of Engineers Aquatic Restoration Monitoring for Ecosystem Recovery (ARMER) Network

Abstract: Long-term, high-quality ecosystem restoration monitoring is essential to achieve recovery and maximize restoration investments. However, there are many challenges associated with restoration monitoring that inhibit effective collection, storage and management, communication, and utilization of ecosystem recovery information. A nationwide monitoring network of restoration and reference sites is needed to generate high-quality, replicated datasets to address large-scale ecosystem restoration challenges. The US Army Corps of Engineers (USACE) makes significant annual investments in ecosystem restoration projects and monitoring for adaptive management under their aquatic ecosystem restoration mission, and thus, is uniquely positioned to lead the development of an ecosystem recovery monitoring network. Investments in large-scale, long-term data collection and management would allow USACE to (1) improve data consistency and data replication to reduce uncertainty in ecological recovery assessments, (2) demonstrate the socioecological benefits of restoration to better inform future restoration investments, and (3) improve the USACE’s ability to publicly communicate returns on investments and the nationwide value of aquatic ecosystem restoration. This report details a roadmap for how USACE could leverage aquatic ecosystem restoration investments to operationalize the USACE Aquatic Restoration Monitoring for Ecosystem Recovery (ARMER) Network and advance the science of aquatic ecosystem restoration.

29 Aug 2025

Monitoring of Understudied Wetlands: State of Knowledge

Abstract: Some wetlands can present unique challenges for mapping and monitoring due to their size, location, foliage architecture, and spectral characteristics. For instance, assessing ecological condition and restoration success using traditional remote-sensing systems in forested and ephemeral wetlands is onerous. Therefore, the purpose of this technical note is to evaluate the state of knowledge and technology related to the use of remote sensing in assessing vegetation dynamics in understudied and hard to monitor wetlands. Ultimately, this exercise will identify data gaps and recommend improvements for analyzing and modeling wetland systems and trends, quantifying disturbance impacts, and assist efficiencies of data collection to improve management decisions, which in turn will help in reaching restoration goals.

9 Jun 2025

Review of Remote-Sensing Methods for Mapping Riparian and Submerged Aquatic Vegetation: Support for Ecosystem Restoration Monitoring and Flood Risk Management

Abstract: Riparian vegetation, defined as multilayered herbaceous and woody plant communities along river margins or bank edges, and freshwater submerged aquatic vegetation (SAV), described as rooted aquatic plants in shallow rivers, lakes, and estuaries, are key factors influencing the connection between river and floodplain systems. These vegetation types are often used as indicators of riparian health. Current data on riparian vegetation and SAV are essential for addressing future water resource needs, particularly for restoration monitoring and flood risk management. The US Army Corps of Engineers (USACE), as the federal government’s largest water resources development and management agency, requires updated monitoring and assessment methods to support the development, utilization, and conservation of water and related resources. Assessing large riparian corridors involves characterizing baseline conditions, habitat extents, vegetation patterns, and health. Vegetation and habitat data are critical for evaluating the effects of project operations, resource management, and restoration outcomes downstream from USACE dams. However, obtaining such data across large, dynamic, and inaccessible river reaches is challenging. Integrating field-based techniques with remote-sensing technology offers opportunities to map larger areas comprehensively and adapt to future water resource needs. This report reviews re-mote sensing methods for mapping riparian and SAV habitats with emphasis on vegetation characteristics.

25 Jul 2024

Regeneration Dynamics of Bottomland Hardwood Sites Following Prolonged Growing-Season Inundation

Abstract: The spring flood of the Mississippi River and backwater areas in 2019 resulted in large-scale flooding and was the longest-lasting flood event since the Great Flood of 1927. This flood event provided a rare opportunity to establish permanent plots in batture and backwater habitats to evaluate forest-stand dynamics following prolonged flooding. In this study, we evaluated postflooding conditions of forest overstory, midstory, and regeneration by establishing permanent plots at four locations subjected to varying amounts of flooding within the Mississippi River batture and the Yazoo–Mississippi Delta backwater region. Our results highlight oak regeneration success following the 2019 flood event as well as the utility and need to establish and monitor permanent plots to increase our understanding of floodplain forest dynamics in regions experiencing prolonged riverine flooding during the growing season.

21 May 2024

Engineering With Nature: An Atlas, Volume 3

Abstract: Engineering With Nature: An Atlas, Volume 3 showcases EWN principles and practices “in action” through 58 projects from around the world. These exemplary projects demonstrate what it means to partner with nature to deliver engineering solutions with triple-win benefits. The collection of projects included were developed and constructed by a large number of government, private sector, nongovernmental organizations, and other organizations. Through the use of photographs and narrative descriptions, the EWN Atlas was developed to inspire interested readers and practitioners with the potential to engineer with nature.

5 Mar 2024

Environmental DNA Sampling for At-Risk and Invasive Species Management on Military Ranges: Guidelines and Protocols for Installation Biologists and Land Managers

Abstract: Environmental DNA (eDNA) analysis, or the detection of trace DNA shed by organisms into their environment, has the potential to transform Army capabilities for threatened and endangered species (TES) and invasive species management by providing a rapid, noninvasive, and cost-effective option for monitoring wildlife. Despite these benefits, eDNA analysis is underutilized on military installations as limited access to guidance materials, protocols, training opportunities, and support from eDNA scientists makes it difficult for installation biologists and military land managers to design and execute eDNA surveys, let alone identify management questions that may benefit from eDNA monitoring. Therefore, the aim of this resource is to increase awareness of the benefits and limitations of eDNA monitoring and provide eDNA study design guidelines and field sampling protocols for nonexperts to make this tool more accessible to installation biologists and land managers and help facilitate the adoption of eDNA-based approaches for wildlife management on military ranges.

9 Feb 2024

Overview of Microscale Analytical Methods for the Quantitative Detection of Bioaccumulative Contaminants in Small Tissue Masses

Abstract: For many bioaccumulation studies, generation of large sample masses of exposed organisms is challenging or even prohibitive. Therefore, the use of smaller sample masses for analysis without compromising data quality or quantitative level achieved is desirable. To this end, a variety of microanalytical procedures have been developed that used 1 g or less of tissue to address specific experimental challenges. However, these methods have not been systematically evaluated or published. The present work evaluates the current state of the microanalytical methods reported and identifies additional needs that would benefit US Army Corps of Engineers (USACE) research and navigation dredging programs. Discussions with commercial laboratories revealed that they typically do not accept small sample masses and require individual sample masses ranging from 10 to 20 g wet weight of tissue per analysis. If they do analyze a small mass sample, they routinely do not modify their standard process, resulting in detection and reporting limits orders of magnitude higher; therefore, essentially useless nondetect data are generated for regulatory decisions. To address the lack of commercial availability of microanalytical methods, we recommend pursuing method development and subsequent validation of microscale extraction and analysis of a variety of common contaminant compounds in tissue matrices.