THE TRAFFIC LIGHT APPROACH
The limit reference point approach where the independent variable measures some indicator of
exploitation rate, leads directly to a monitoring system for the resource or environment where the
rate of harvesting in relation to at least 2 reference points can be specified. Where several indicator
series are available, these may be plotted on the same page showing the trajectory of the fishery as
monitored by different indicator series. Simplifying the interpretation of such multi-series charts,
colours can be added to provide information directly on stock status (healthy or safe = green ;
uncertain = yellow; dangerous = red). The result of this procedure is a resource monitoring system
that can control physical, biological and environmental series of importance simultaneously, and is
referred to as a ‘Traffic Light Approach’. This approach was first developed for the invertebrate
fisheries of the NAFO area, where the absence of age-reading capability prevented application of
the cohort analyses commonly used for finfish stocks.
TL8)_______(2007). Comments by J.F. Caddy on the traffic light analysis for Northern shrimp.
Annex 3 of Canadian Science Advisory Secretariat (CSAS) Proceedings Series 2007/034.
TL7) Caddy, J.F. (2006). The potential use of indicators, reference points and the traffic light
convention for managing Black Sea fisheries. P 1-23 In: G. Lembo (ed): Selected papers presented
at the workshop on biological reference points, Rome, 20-21 April 2004. GFCM Studies and
Reviews No 83, 80p.
TL6)___________and T. Surette. (2005). In retrospect the assumption of sustainability for Atlantic
fisheries has proved an illusion. Revs. Fish. Biol. Fisheries 15; pp 313-337.
TL5) Seijo, J.C. J.F. Caddy and W. Arzápalo. (2006). Some considerations for an ecosystem
approach to management in the Southern Gulf of México. In: J. W. Day & A. Yáñez-Arancibia
(eds.), The Gulf of Mexico: Ecosystem-Based Management. The Gulf of Mexico: Its Origin,
Waters, Biota, Economics & Human Impacts (Series). Harte Research Institute for Gulf of Mexico
Studies, Texas A&M University - Corpus Christi.
TL4)_________E. Wade, T. Surette, M. Hebert and M. Moriyasu. (2005). Using an empirical
traffic light procedure for monitoring and forecasting in the Gulf of St. Lawrence fishery for the
snow crab, Chionoecetes opilio. Fisheries Research, Vol. 76 (1) October 2005. pp 123-145.
TL3)________(2005). The potential use of indicators, reference points and the traffic light
convention for managing Black Sea fisheries. Paper presented at the GFCM/SAC Workshop on
Reference Points for Mediterranean Fisheries, Rome, Italy, 20-21 April 2004.Genereral Fisheries
Commission for the Mediterranean, Studies and Reviews, in press.
TL2) ________(2002) Viewpoint: Limit reference points, traffic lights, and holistic approaches to
fisheries management with minimal stock assessment input – a personal viewpoint. J. Fish. Res. 56.
p133-137.
TL1)__________ (1998). Deciding on precautionary management measures for a stock and
appropriate limit reference points (LRPs) as a basis for a multi-LRP harvest law. NAFO SCR Doc.
No. 8, SN 2983, R.D.