Marine fisheries are acknowledged to be some of the most important food
resources for countries around the world. However, the issue of fishery
sustainability has now become a key concern around the world. As
reported by World Wild Fund for Nature (WWF), cod are currently at risk
from overfishing in the UK, Canada and most other Atlantic countries.
Global cod catch has suffered a 70% drop over the last 30 years, and if
this trend continues, the world's cod stocks will disappear in 15 years.
Illegal, unreported, and unregulated (IUU) fishing is one of the major
threats to the sustainability of ocean fish resources. As estimated by
National Oceanic and Atmospheric Administration (NOAA), IUU fishing
produces between 11 and 26 million tons of seafood annually,
representing as much as 40 percent of the total catch in some fisheries.
The driver behind IUU fishing is high economic profit and low chance of
It is impossible to maintain a 24/7 presence to prevent IUU fishing
everywhere due to the limited asset patrolling resources. Hence the
allocation of the patrolling resources becomes a key challenge for
security agencies like USCG. Research within this project aims to
address the problem of deriving accurate patrol schedules for the US
Coast Guard. To achieve this, our aim is to develop fast and effective
techniques to solve security games defined over continuous spaces, where
different types of defenders and attackers might co-exist and
potentially coordinate their behavior.
Above, the airstrip at the Corpus Christi Coast Guard base is pictured, along with team-member Will Haskell.
Aerial assets have much greater range and vision than
surface assets, and are a vital part of CG patrols. Aircraft fly out of
Corpus Christi regularly to patrol the Mexican border.
Despite the importance of air assets, only surface assets
can interdict illegal fisherman. Above, a CG patrol boat is pictured
approaching a suspicious fishing vessel.
There is a large variety of CG surface assets, with
various ranges, speeds and mission profiles. A smaller CG patrol boat
is pictured above, such craft are good for short range interception but
not for long term missions.
Above, a short range patrol boat is pictured leaving the
dock. Vessels of this size can operate away from base for a few hours,
while larger cutters can operate independently for days or weeks.
The CG inspect a seized fishing vessel back at their base.
The fishing vessels used by Lanchas are actually fairly small, two or
three person craft.
The CG pull up alongside a small fishing vessel for an inspection.
Game Theoretic Fish Patrol Schedule Model Overview
The Game Theoretic Fish Patrol Schedule Model casts the interaction between the USCG (defender) and the illegal fishing boats, i.e., lanchas (adversaries), as a repeated Stackelberg game. Real-world data provided by the USCG is used to estimate the parameters of the game, including the behavorial model of the Lancha adversaries. The Stackelberg game can be solved using the MIDAS algorithm which computes the defender's strategy, i.e., a randomized patrolling strategy. The defender strategy is then used to generate daily patrol schedules for the USCG assets. Executing these patrol schedules produces more Lancha data which allows the entire process to be repeated .
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necessarily reflect the views of the USCG, DHS, or the U.S. Federal
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