Don’t know a fluke from a mushroom? Then this quick guide to anchors is for you.
Whether a fisherman is trying to stay over a favorite spot or a ’toon commander is looking for the perfect anchorage for lunch, having the proper ground tackle on board to hold the boat in place is an indispensable part of everyday boating. Even for folks who typically don’t anchor, having an anchor ready to deploy in the event of an emergency is not only crucial but just plain good seamanship. Here’s a look at common anchor types and how to choose the right one.
Most anchors are fitted with a combination rode, which consists of a short length of chain and a long nylon line or rode. The chain adds weight to the rode, which increases the horizontal pull and helps the anchor remain set. It also protects the rope rode from chafe and wear. Nylon is preferred because it stretches, which allows the rode to absorb the sudden loads and jerks of a boat bouncing around in the waves.
Manufacturers publish tables to help boat owners select the correctly sized anchor, but a common rule of thumb for steel and cast-iron anchors is roughly one pound of weight for every foot of vessel. Boat owners buying an anchor should probably avoid imitations and stick with the name brands. They cost more initially, but a quality anchor will pay for itself many times over in security and peace of mind.
Anchor Types & Selection
Anchor selection is based on a number of factors. The type of bottom (mud, grass, sand, rock), windage of the boat, and wind and water conditions are all factors to consider. Anchors themselves come in a number of styles; however, they’re all designed to hold a boat by using the weight of the anchor and hooking it to the bottom or burying it into the bottom, or a combination of all three. While an anchor’s weight is important, even more so is its holding power — how well the anchor digs in and holds. A modern, well-designed, lightweight anchor can provide significantly more holding power than a heavy, older model that relies more on weight. It’s important to know the common anchor types and a few of the pros and cons associated with each.
Traditional Danforth anchors and the newer aluminum-magnesium alloy Fortress Marine anchors with adjustable fluke angles are popular examples of fluke anchors. Their large flukes hold well in clay, mud and sand but are less effective in rocks and grass. A pipe-like stock keeps the anchor from twisting and pulling out as the boat shifts, but if the direction of pull goes past 180 degrees, the anchor will most likely break free — and usually reset itself in the new direction. While its lighter design is attractive, a fluke anchor can be awkward to stow, and it has a lot of angles that can snag lines and toes. As such, fluke anchors are a popular choice for boats with a dedicated anchor locker — bowriders, midsize and larger fishing boats, etc. They’re also popular with pontoon owners.
The plow is a stockless, single-point anchor that is so-named because of its shape, which resembles the plows farmers use. Popular examples include the CQR (a name derived from “secure”), Rocna, Delta, and Manson Supreme anchors. Plow anchors perform well in sand, stiff mud, grass and shell bottoms, but are less effective in soft mud or clay. Many boaters consider a plow anchor to be the ideal overall anchor for vessels longer than 30 feet, and while it may not be the best in any one type of bottom, it holds well in all of them. Plow anchors, which are typically heavier and bulkier than Danforth anchors, are easiest to stow and deploy on boats with a bow roller and a dedicated anchor locker.
Although similar to the plow, instead of a single point of penetration, claw anchors have a scoop design. The Bruce and the Lewmar Claw are good examples. Claw anchors perform well in a wide variety of bottom types (sand, mud, grass) but are not ideal for rocky bottoms. Like the plow, they’re more easily stowed and deployed on boats with a bow roller and a dedicated anchor locker, due to their size and weight.
Grapnel anchors typically have at least four large arms, or flukes, and work best on rocky or weedy bottoms, where their arms can hook something. They’re particularly useful in heavy vegetation, where one or more flukes can penetrate the bottom, while the outside ones can hook into the surface vegetation. While they excel in rocks and weeds, they should be considered a temporary anchoring solution in most other cases.
Grapnel anchors are popular choices for smaller craft — dinghies, kayaks, PWCs — due to their light weight and ease of stowing. Most have folding arms and can be tucked away in a surprisingly small space.
Spike or “grabber’ anchors are a variation of the grapnel anchor but typically have five or more shorter, fixed spikes or prongs attached to a centrally weighed shaft or base. They have more heft than a similarly sized grapnel, but since the arms are fixed they can be more of a pain to stow.
Shallow Water Anchor
While not an anchor in the traditional sense, the Power-Pole is a flexible spike that lets anglers silently “spud down” over a favorite shallow-water anchorage (8 feet or less). The spike is deployed via a push button–operated folding hydraulic arm. One Power-Pole can hold a boat in place, but two allow a boat owner to position the boat in the most favorable position regardless of prevailing wind and current.
While typically found on bass boats, they can be installed on most any fishing boat that anchors regularly in shallow water.
Named for their shape, mushroom anchors resemble an upside down mushroom. Their holding power comes from their weight and the bottom suction they generate once they’re buried, which is why they are often used as mooring anchors. Many models have holes or slits in the circular bowl or “cap” area, to help release the suction during retrieval.
Ideal for canoes, Jon boats and other small craft, mushroom anchors work best in silt or mud bottoms, but not where they will have trouble burying themselves (e.g., rocks, weeds).
Derived from the mushroom anchor, River anchors are similar in shape but have broad flukes rather than a mushroom cap. The flukes, which have rounded rather than pointed ends, allow the anchor to penetrate the bottom better than mushroom anchors. They also improve the anchor’s ability to grab and hold, meaning river anchors not only work well for soft bottoms but in a pinch can give decent service on rougher bottoms such as weeds and rocks. They’re good for use aboard canoes, Jon boats and similar small craft.
Another anchor with a shape-derived name, the Box anchor is a square unit with eight angled flukes — four per side, two each at the front and back. Box anchors provide holding power by maximizing surface area contact with the bottom. Once deployed, the anchor’s scoop design allows the narrow panels to set, cookie-cutter like, into muddy bottoms.
Especially popular with pontoon owners, a Box anchor requires no chain, sets quickly, retrieves easily and folds flat for storage.
Traditional anchors still do the job for boats large and small, and they aren’t going anywhere anytime soon, but technology has given boaters a new way to anchor, and it doesn’t even involve being attached to the bottom.
While safety and common sense dictate that every boat carries a suitable anchor and rode at all times, virtual anchoring has come to town, and it’s pretty damn cool!
Minn Kota’s i-Pilot features Spot-lock, a GPS anchor that keeps the boat in position over a favorite fishing spot. With i-Pilot iTracks, anglers can return to the same spot (or spots) with the push of a button. Spot-lock, which makes use of i-Pilot’s internal GPS receiver, maintains the trolling motor within a 5-foot circle of a GPS-identified position. If current, wind or waves move the trolling motor out of that 5-foot circle, i-Pilot automatically adjusts prop speed and direction to return to the 5-foot circle. Once back in the circle, i-Pilot will adjust the motor speed to zero. MotorGuide and Rhodan also offer trolling motors with virtual anchoring.
Joystick docking is red hot right now, and most joystick systems offer a stationkeeping feature such as Skyhook from Mercury and MerCruiser, which acts as a digital anchor that locks a boat’s position using GPS technology. Automatically working with both outboards and sterndrives, the system maintains the boat’s position and heading regardless of wind or current. Such a function comes in imminently useful while fishing, waiting for a bridge to open or sitting in line at the fuel dock. It’s also easy to operate; simply place the levers in neutral and push the Skyhook button to lock position and heading. SeaStar Solutions’ Optimus 360 for outboards and Volvo Penta’s Dynamic Positioning System for its IPS pod drives also offer this useful innovation.
Virtual anchoring makes it easy to stay in one location — or several over the course of the day — without having to deploy an actual anchor every time.