Jason Runnells.

Crossing the Line

A spatial analysis of Island Packers vessel traffic within the Channel Islands National Marine Sanctuary and Marine Protected Areas

Jason Runnells | February 13, 2025

Overview

This project explores the spatial relationship between commercial vessel traffic and protected marine areas within the Channel Islands region. Using over a year of Automatic Identification System (AIS) tracking data, it quantifies how often Island Packers vessels—contracted operators for Channel Islands National Park—enter the boundaries of the Channel Islands National Marine Sanctuary (CINMS) and its Marine Protected Areas (MPAs).

Through this analysis, patterns of activity emerge across the company's four primary vessels, revealing how tourism intersects with zones meant to safeguard fragile ecosystems. Special attention is given to the Vanguard, a smaller, older vessel with a disproportionately high rate of MPA intersections despite making fewer trips. The findings demonstrate how spatial analysis can inform ecological stewardship and highlight areas of potential concern in balancing conservation with access.

Questions

• Where does Island Packers' vessel traffic occur within the Channel Islands National Marine Sanctuary and its Marine Protected Areas?
• To what extent do individual vessel trips intersect with protected marine zones, and how do these intersections vary across different vessels?

Channel Islands

Located off the coast of southern California, the Channel Islands and their surrounding waters support some of the most ecologically diverse habitats in the world. From iconic species like the island fox to expansive kelp forests teeming with sea lions, whales, and dolphins, this remote archipelago offers a unique convergence of land and marine biodiversity—much of it found nowhere else on Earth.

Marine Protected Areas

Marine Protected Areas (MPAs) are zones established to conserve marine ecosystems by managing human activity within their boundaries. NOAA defines an MPA as "a clearly defined geographical space, recognized, dedicated, and managed... to achieve the long-term conservation of nature with associated ecosystem services."

The California Department of Fish and Wildlife further describes MPAs as areas designed to protect marine biodiversity, habitats, and ecological integrity while supporting sustainable use where appropriate.

Island Packers

Methodology

This analysis uses over a year of AIS vessel tracking data to quantify how often Island Packers vessels intersect protected marine zones. By examining the movement of each vessel across CINMS and MPA boundaries, the project identifies spatial patterns that reveal how tourism activity interacts with conservation efforts.

How the Data Was Collected

Each Island Packers vessel transmits a unique Maritime Mobile Service Identity (MMSI) via the Automatic Identification System (AIS), a real-time tracking signal required for commercial operations. These signals are received by the U.S. Coast Guard and distributed through NOAA's Marine Cadastre platform, making it possible to visualize and analyze vessel movements.

Handling Signal Gaps

Because AIS signals can occasionally drop due to terrain, interference, or equipment issues, some vessel tracks appear incomplete. To prevent double-counting, tracks were evaluated by timestamp and location. If two or more segments were determined to belong to the same trip, they were merged and counted once.

Defining an Intersection

A vessel trip was considered to have "intersected" a protected area if any part of its track entered the boundary of CINMS or one of the four MPAs. Even if a vessel entered and exited the same zone multiple times on a single trip, only one intersection was recorded to avoid inflating the results.

Spatial Analysis

This section presents the results of the spatial analysis conducted on over a year of AIS vessel data. It highlights how often Island Packers vessels intersect with protected marine zones, using both cumulative statistics and individual vessel comparisons to illustrate patterns of interaction with the Channel Islands National Marine Sanctuary and its Marine Protected Areas.

Vessel Intersections

The following sections present vessel-specific spatial statistics for the Island Packers fleet. Each entry includes a map of recorded AIS tracks and a summary of how often the vessel intersected the Channel Islands National Marine Sanctuary (CINMS) and its protected zones. These comparisons help illustrate the role each vessel plays in shaping patterns of marine area interaction.

Statistical Analysis

Over the 13-month study period, Island Packers vessels recorded a combined total of 3,599 intersections with the Channel Islands National Marine Sanctuary (CINMS). Because all Marine Protected Areas (MPAs) in this analysis are nested within the CINMS boundary, these totals also reflect the number of unique trips evaluated.

The Island Adventure had the highest number of CINMS intersections, while the Islander and Island Explorer followed closely behind. The Vanguard, although responsible for less than half the number of trips compared to the other vessels, had an unusually high number of MPA intersections—only 9% fewer than the Island Adventure.

This anomaly is likely tied to its route: the Vanguard primarily services Anacapa Island, which is the only island in this study containing all four MPA designations. This concentrated overlap illustrates how route specialization and destination can be just as influential as overall trip volume in shaping protected area impact.

Emissions Context

While the primary focus of this project is spatial intersection, emissions are an important secondary consideration when evaluating the environmental impact of commercial vessel traffic in protected areas. The vessels used by Island Packers are diesel-powered, and depending on age and engine type, may emit varying levels of particulate matter, nitrogen oxides (NOₓ), and other pollutants.

Although detailed emissions estimates were not calculated as part of this analysis, vessel registry records and manufacturer data suggest that older vessels, such as the Vanguard, are likely to be less fuel-efficient and more polluting than newer models. The Vanguard's elevated intersection count, combined with its older diesel engine, may make its operations particularly impactful to fragile marine ecosystems.

Incorporating emissions modeling into future studies could strengthen understanding of how vessel traffic contributes to cumulative environmental stress in protected marine zones.

Conclusion

This project highlights the value of spatial analysis in understanding how commercial tourism activity interacts with protected marine environments. By quantifying vessel intersections with the Channel Islands National Marine Sanctuary (CINMS) and associated Marine Protected Areas (MPAs), clear patterns emerged across different vessels, routes, and destinations.

The findings point to areas where conservation and access may be in tension—particularly around Anacapa Island, where the overlap of all four MPA designations and high vessel activity call for closer scrutiny. They also underscore how vessel-specific behavior, not just trip volume, can shape ecological impact.

While this study does not establish causation or directly assess ecosystem degradation, it provides a foundational framework for further analysis and policy consideration. Protecting fragile marine environments requires not only monitoring but thoughtful, data-driven action—and tools like AIS tracking offer a powerful lens through which to view and manage that relationship.