FAQ

The GPS numbers we list on our maps are in degrees and decimal minutes (DD° MM.MM’), which is also the default format used by most chartplotters.

Most chartplotters have a place for a third decimal number (DD° MM.MMM’), so just add a zero onto the end of our numbers when inputting into your GPS unit (e.g., 32° 12.50’ is the same as 32° 12.500’).

GPS numbers can be listed in decimal degrees (DD.DDD°), degrees and decimal minutes (DD° MM.MMM’), or degrees minutes seconds (DD° MM’ SS”).

Our map grids are based on degrees and decimal minutes, as that is the default format used by most chartplotters. You can convert from degrees minutes seconds by dividing the number of seconds you have by 60 and adding the resulting decimal to the number of minutes. For example, 33° 12’ 30” is the same as 33° 12.5’. Note this calculation has no effect on the degrees.

There are 60 seconds (“) in a minute (‘) and 60 minutes (‘) in a degree (°).

Topographic maps of the sea floor. Underwater features are vividly portrayed through the full use of bathymetric data on our maps, not filtered for navigation information like a NOAA chart.

A chart’s primary purpose is to aid in navigation, while a map serves as a reference guide. Our maps are intended to present bottom detail and other pertinent information to the private boater, rather than to enhance the safety of navigators.

We don't keep a running tally of obstructions to navigation in the Southern California Bight. That's the Coast Guard's job. What we do provide is a large-scale map with a GPS grid overlay, so you can pinpoint the GPS location of any feature on the map.

MHW = Mean High Water. That means the depths represented by contours on the map are in reference to the average high tide. Therefore, if the existing height of tide is below MHW, the actual depths will be less than shown on the map.

No. The shoreline shown on our maps represents the line of contact between the land and water at the average high-water line (MHW).

No. Our maps were not intended to be used underwater while diving. The holes punched in the laminate will let water soak in if submerged in water for any length of time.

The scale of a map is the ratio of a given distance on the map to the actual distance which it represents on the earth. For example, 1:20,000 or 1/20,000 means that one unit (such as an inch) on the map represents 20,000 of the same units on the surface of the earth.

A map covering a relatively large area is called a small-scale map (e.g., 1:XXX,XXX) and one covering a relatively small area is called a large-scale map (e.g., 1:X,XXX). As scale increases, the amount of detail which can be shown increases as well.

To plot correctly, GPS positions must be on the same datum as the map being used, or they could be hundreds of yards off. Most chartplotters use the WGS 84 datum by default, so that is what we use on our maps.

The compass rose is a graduated scale printed on a navigation chart which can be used by the mariner to plot a course on the map. A compass rose is a circle graduated in degrees, clockwise from 0° at the origin to 359° and can include compass points (N, S, E, W). The compass rose on a NOAA chart shows two graduated scales. The outer circle is referenced to True North and the GPS grid on the chart, while the inner circle is referenced to Magnetic North.

A fishing map is a detailed bathymetric map of the ocean floor designed primarily to aid fishermen and other users in the identification of seafloor features and the location of potential fishing grounds.

You can use the calibrated grid to plot GPS coordinates of any fishy-looking feature on the map. Just use two straight edges (like from lure packaging or a lobster gauge) to line up the latitude and longitude on the map. You can then plug the coordinates into your chart plotter to take you right to the spot. Simple as that.

A fishing map has information specific to fishing and shows the ocean bottom in greater detail. Depths on any given NOAA chart may be based, in some areas, on hydrographic surveys conducted with leadlines (literally a line with lead at the end, scope et. al.) prior to 1900. Recent surveys with modern GPS and multibeam survey instrumentation provide much better coverage of the seafloor and are what we use on our maps.

The 50-fathom boundary used by CDFW for general groundfish management in the Southern Management Area is defined by federal regulations that spell out the depth limit as GPS coordinates. The restriction is not based on the true depth of water, but whether a physical line established by a series of waypoints has been crossed. The gps coordinates are listed by the National Marine Fisheries Service in their Groundfish Regulations 50 CFR Part 660, Subpart C. You can look them up and plot the coordinates yourself, or buy one of our maps where they are listed for you.

No, the depth limit for groundfish has changed over the years and is always subject to in-season change. Call the Recreational Groundfish Fishing Regulations Hotline at (831) 649-2801, or visit the CDFW website for the latest information. Also, the depth limit for bottom fishing inside Southern California’s Cowcod Conservation Areas is 240 feet, again a physical line established by a series of GPS waypoints and not as measured by depth. We note that on the map where applicable.

Groundfish refers to the RCG complex of fish, as defined by the California Department of Fish & Wildlife as “all species of rockfishes, cabezon and greenlings [lingcod, etc.].” Other species like ocean whitefish, sheepshead and sculpin are also listed. Please call the Recreational Groundfish Fishing Regulations Hotline at (831) 649-2801, or visit the CDFW website for the latest information.

MLPA is an acronym for the Marine Life Protection Act which was passed by California Legislature in 1999. The specific areas targeted by the Marine Life Protection Act are referred to as Marine Protected Areas (MPAs).

Not necessarily, the three types of MPAs specify different levels of restrictions. Some State Marine Conservation Areas (SMCAs) for example are completely open to traditional hook and line sport fishing and regular bag limits apply.

No. MPA law defines “take” as not just keeping fish, but catching or trying to catch them as well. This means you cannot even put a line in the water when inside an MPA zone closed to hook and line sport fishing.

Chumming would be considered feeding of fish under MPA law and is prohibited unless otherwise specified. Note that in Southern California only two MPAs specifically authorize feeding of fish for purposes of marine life viewing. Both are in Avalon Bay at Catalina Island: Casino Point SMCA (No-Take) and Lover’s Cove SMCA.

No. MPA regulations define coastal pelagics as anchovy, sardine, mackerel and market squid. Think coastal pelagic = bait.

MPA regulations define pelagic finfish as: anchovy, mackerel, sardine, barracuda, striped marlin, swordfish, dorado, tuna, yellowtail, salmon, blue shark, mako shark and thresher sharks.

No. MPA regulations specify different restrictions according to different gear types: hook and line, spearfishing and hand-held dip net.

Yes. Anchoring inside an MPA with legal catch onboard is allowed unless otherwise specified. Fishing gear should not be deployed in the water at any time while within the boundaries of any MPA that doesn’t specify an exception.

Yes. Transit through MPAs with legally caught fish on board is allowed. Fishing gear should not be deployed in the water at any time while within the boundaries of any MPA that doesn’t specify an exception.

You can drift through a closed area with legally caught fish on board as long as there is no fishing gear deployed while inside the closure.

There are two types of MPAs in Southern California: State Marine Reserves (SMRs) and State Marine Conservation Areas (SMCAs). The SMCAs have two different classifications however and one is classified as SMCA (No-Take).

SMCAs that are classified as no-take are closed to direct fishing methods yet offer some level of incidental take during authorized and permitted operations, such as sand re-nourishment or maintenance of artificial structures.

MPA law states that public access into marine protected areas is allowed for non-consumptive use, unless otherwise specified. This includes, but is not limited to swimming, surfing, diving, boating, hiking and walking.

Not necessarily, MPA law prohibits all forms of commercial and recreational take unless otherwise specified. Some MPAs are open to take of specific species by specific gear types. Farnsworth Onshore SMCA for example is closed to traditional hook and line sport fishing, but is open to spearfishing for pelagic finfish, white sea bass and bonito.

Not necessarily. All MPAs are closed to bait fishing unless otherwise specified. Some SMCAs specify bait fishing is allowed, but only with hand-held dip net. Under these circumstances fishing with sabiki rigs or squid jigs is not allowed.

Yes. For practical purposes consider the barbs of a squid jig as a hook. Under MPA law a squid jig cannot be used in an area closed to hook and line sport fishing.