ONMS Sentinel Site Program FAQs

The name "National Marine Sanctuary" is reserved for special ocean places with exceptional natural, archaeological, or cultural value. NOAA, through the Office of National Marine Sanctuaries, is responsible for protecting these places. It uses science, education, outreach, enforcement and resource protection programs to conserve, protect, and enhance their biodiversity, ecological integrity and cultural legacy. Conservation science and maritime heritage programs help us understand the influence of humans on sanctuary resources, and we use these programs to inform decisions about pressing issues facing sanctuaries, such as fishing and fisheries, vessel traffic, noise production, visitation, and other human activities.

1. Why do we call national marine sanctuaries "sentinel sites"?

National marine sanctuaries are places where focused monitoring and research efforts take place that enhance our understanding of natural and historical resources and how they are changing. This allows them to serve as sentinel sites that provide early warning capabilities for detecting changes to ecosystem processes and conditions.

Marine sanctuaries are located across the country, and thus offer the opportunity to monitor, observe, and research on local, regional, and national scales.  Ecosystem resources are diverse and their conditions vary substantially, thus offering limitless research and monitoring opportunities.  Sanctuaries provide a sense of place that stimulates interest, curiosity, and investment about the world and its diverse inhabitants and habitats.

Marine sanctuaries are places where government, academic and citizen scientists work collectively and share information on sanctuary conditions and emerging threats. Work within sentinel sites provides early warning capabilities that give us an advantage over threats by allowing us to respond before problems get beyond our control. Quite simply, sentinel sites help us all achieve our collective goal of protecting our nation's most cherished ocean treasures.

We believe that identifying sanctuaries as sentinel sites, and developing a "Sentinel Site Program," not only recognizes the purposeful vigilance of our efforts, but also helps NOAA attract needed collaborators, improve information flow, interpret science to the public, and in general, advance conservation science through our collective assets and efforts.

2. What is the connection between ONMS and other NOAA sentinel site efforts?

There are several activities within NOAA that use the term "sentinel" as part of their description. One focuses on sea level monitoring and uses regional partnerships called "cooperatives" for implementation. Another is a system of "NOAA Sentinels," which are permanent instrument towers that measure and disseminate real-time water level and weather observations. The National Estuarine Research Reserves are also developing a sentinel site approach to monitoring (PDF). So "Sentinel Sites" is really an umbrella concept within NOAA, with individual programs customizing their own efforts to meet particular science, service, and stewardship needs.

In the future, it is likely that NOAA will expand its sentinel sites activities to address other issues of concern, including, for example, ocean acidification, noise, and invasive species. In each case, networks of observing sites will be needed, located strategically to gather and integrate information and data streams to understand changing conditions at specific temporal and spatial scales that are relevant to science and management priorities. Marine sanctuaries will be part of these sentinel networks, contributing observational data and facilitating research.

3. What issues do sentinel sites address?

Sentinel sites focus conservation science on issues and threats that are common to multiple sanctuaries. Examples include condition of key species;; climate change and ocean acidification; fishing impacts; human health; invasive species; marine debris; noise; integrity of heritage resources; vessel impacts; and water quality. Among the many issues that could be selected, each of these met several criteria that raise our level of concern: high impact to archaeological resources; high ecological impact; high economic impact; widespread geographic interest ; high interest to stakeholders; complementary to other issues; and high level of urgency.

Condition of Key Species:

For "key" species in marine sanctuaries (e.g., keystone species, indicator species, and protected species) measures of condition and health can be important in determining the likelihood that these species will persist and continue to fulfill vital ecosystem functions. Measures of condition may include growth rates, fecundity, recruitment, age-specific survival, tissue contaminant levels, pathologies (disease incidence tumors, deformities), the presence and abundance of critical symbionts or parasite loads.

Climate Change and Ocean Acidification:

On global and regional scales, the ocean is changing due to increasing atmospheric carbon dioxide and associated global climate change. Physical changes include sea level rise, coastal erosion and flooding, as well as changes in precipitation and runoff, storm frequency and intensity, ocean-atmosphere circulation, and ocean water properties including temperature. Ocean acidification is a change in the ocean's chemistry caused by increased amounts of carbon dioxide leading to increasingly acidic conditions. Ocean acidification can affect organisms whose structural components contain calcium carbonate.

Fishing Impacts:

Fishing activities affect sanctuary resources through direct take, by-catch, and habitat damage from the use and loss of fishing gear. The removal of targeted species and coincident mortality of non-target species (by-catch) may result in complex and confounded ecological effects.

Human Health:

Human health concerns include contamination (usually bacterial or chemical) in water used for recreation or in fish intended for consumption. Other examples of concerns are health related impacts from harmful algal blooms and ciquatera fish poisoning.

Invasive Species:

Invasive species impact the diversity or abundance of native species or the ecological stability of infested waters, or commercial, agricultural, aquacultural, or recreational activities in the vicinity.

Marine Debris:

Marine debris can include a wide variety of objects (e.g., construction materials, derelict fishing gear, lost vessel cargo and plastics) and can threaten the marine environment and resources, human health, and navigation. Some examples of impacts from marine debris include death to marine organisms through ingestion and entanglement as well as altered habitat structure.


Major sources of human-generated sound in marine environments include ships and other motorized vessels, military underwater communication, sonar, airguns, and low flying aircraft. Noise can affect living resources both physiologically and behaviorally through impacts on hearing or tissue integrity, and disruption in resting, feeding, courtship, calving, nursing, navigation, communication.

Integrity of Heritage Resources:

Historical significance of an archaeological resource depends on its integrity and/or its representativeness of important past events, its association with important persons, or its embodiment of a distinctive type of architecture. Thus the condition of archaeological resources significantly affects their value for science and education. In addition, deteriorating modern artifacts (particularly sunken vessels and aircraft) occasionally release fuel and other cargo that could pose a pollution threat to coastal and marine resources. Knowing where these vessels are helps oil response planning efforts and may help in the investigation of reported mystery spills (sightings of pollution where a source is not immediately known or suspected).

Vessel Impacts:

Visitors, scientists, fishermen, commercial shippers, and other stakeholders of the National Marine Sanctuaries access the sanctuary through the use of recreational and commercial vessels. These vessels are an important part of the "blue economy" and also provide a safe way for many visitors to experience some of the sanctuaries most iconic places. However, there are several impacts from vessels that can impact biological and archaeological resources within the sanctuary. These impacts include ship strikes, ship groundings, lost containers from shipping vessels, and discharge of waste water and other materials.

Water Quality:

Water Quality and the risk posed by contaminants and other potential stressors in water or in bottom formations needs to be understood and tracked if it is to be controlled. Contaminants in the form of pesticides, hydrocarbons, and heavy metals can become available when released via disturbance and can impact water quality. Excessive sedimentation can cause direct impacts, such as smothering or interfering with feeding. Elevated nutrient loads commonly enhance algae growth, gradually altering food webs or spatial distributions of wildlife, or leading to blooms that can release toxins and reduce oxygen levels.

4. Why should you be part of the ONMS Sentinel Site Program?

Working with sanctuary and partner scientists provides opportunities to make a difference on issues that are important for ocean conservation. It can also build connections to NOAA offices, state, local and tribal governments, and academic and NGO partners. It opens access to data, information, and logistical support that can help you design and implement your research. And it could help you target research to address important gaps in knowledge, making your research even more applicable to conservation efforts. It's also likely that these associations will help you identify and compete successfully for related funding opportunities.

5. What activities are currently in place?

Many activities that support the goals of a functional sentinel monitoring program already occur within the sanctuary system. Many are summarized in the Sanctuary Monitoring Inventory and depending on the sanctuary, may include regular benthic, fish, and plankton censuses, beach surveys, water quality measurements, tracking of seasonal events (e.g., whale migrations and mass spawning), and pollutant monitoring. A few instruments even collect and transmit real-time data streams. Citizen scientists are active in most sanctuaries and are trained to assist in various monitoring efforts as "science assistants" that collaborate with sanctuary staff or partners. A diverse network of people is engaged in monitoring activities that help us understand and predict natural and human-caused changes throughout the sanctuary system.

Monitoring, characterization, and research efforts that address the issues above are all part of the Sentinel Site Program. Observations come mainly from instruments at sea, overflights, satellites, diving and shipboard scientists, remotely operated vehicles and submersibles, and citizens who volunteer their services. A fully functioning sentinel monitoring program, however, doesn't stop with observing;  it includes a continuum of activities that include observing, applied research, modeling and predictions, tools to visualize and analyze data, information sharing, support for management decisions, and education and outreach.

6. What is conservation science?

Conservation science is the gathering of knowledge about human influences on ecosystem structure and function in order to track change, respond to threats, and evaluate the effectiveness of management actions. Disciplines within the ONMS' Conservation Science Program, such as natural sciences, socioeconomics, and maritime heritage, directly support management of the sanctuary system, and address the needs and interests of local communities invested in the viability of sanctuary resources.  ONMS conducts and sponsors natural and social science programs, and facilitates collaborations to better understand ecosystems and cultural resources in marine sanctuaries, their changing condition, and the significance of natural and human-caused threats.  It uses conservation science to support policy decisions, develop effective response capabilities, evaluate management practices, and strengthen the role of the sanctuary system to support NOAA's broader science, service and stewardship missions.

7. How does the Conservation Science Program work?

All sanctuaries coordinate staff activities to address their responsibility to maintain or improve resource condition.  Sanctuary Research Coordinators work with partners to design, implement, and conduct monitoring, characterization, and applied research that address priority concerns.  Education staff helps communicate science through various education programs and outreach events.  Permit coordinators help ensure access to required resources while minimizing impacts to the sanctuary. Resource protection staff manages sanctuary issues through regulations, permitting, incident response and contingency planning, damage assessment and restoration, and enforcement. Maritime Heritage personnel study, protect and promote the diverse legacy of submerged cultural resources within sanctuary waters.

All sanctuaries rely heavily on the work of research partners and volunteers.  Partnerships with universities, public and private research centers, government agencies, international groups, and non-profit organizations, are relied on to characterize, monitor and study sanctuary waters, habitats, wildlife, and the human footprint.  Volunteers contribute a total of over 100,000 hours of service annually to the sanctuaries in areas of research, monitoring, enforcement, education and outreach, and management advisory.

8. Where can I find the results of sanctuary science?

We report science findings primarily in published literature, technical reports, and on the web. Some of the most heavily used by decision-makers are sanctuary management plans, condition reports, science plans, and science needs assessments. Many of these documents can be found on our website. There is also a series of technical reports called the Marine Sanctuaries Conservation Series.

Management Plans are site-specific documents used to manage individual sanctuaries.  They articulate the visions, goals, objectives, and priorities; summarize existing programs and regulations; provide actions to address specific needs; and guide the preparation of annual operating plans.

Condition Reports summarize sanctuary resources, human pressures on those resources, current conditions and trends, and management responses to the pressures that threaten the integrity of the marine environment. They include information on the status and trends of water quality, habitat, wildlife, archaeological resources and the human activities that affect them. The reports serve as a tool to gauge progress toward resource protection and improvement goals.

Science Plans identify and prioritize the scientific needs of the sanctuaries, and provide guidance for future research and monitoring.

The Science Needs Assessment provides targeted information on the science requirements of the sanctuary system based on the management issues defined in the program documents previously mentioned. The assessment supports sanctuary science and management staff working to address these requirements, and communicates these needs to potential partners and interested organizations and individuals.

9. How will sentinel sites help sanctuaries address issues of concern?

Sentinel sites are locations where research and monitoring efforts are specifically intended and designed to focus on priority concerns of the marine sanctuaries. The are places that partners are encouraged to consider for their work. Issues are described both in the sentinel site website and within the science needs assessment for each marine sanctuary. We encourage scientists to address these needs and facilitate their work, when possible. In many cases, sentinel sites are also locations with multiple ongoing studies, the data from each potentially complementing others. This minimizes duplication and improves use and access to data for all users.