Very rarely are sea cargo vessels owned or wholly leased by single agencies that also solely utilise them for their own shipping purposes. The overall size, cost, time and general nature of sea freight necessitates that no single entity but those with massive and regular volumes of cargo could ever utilise an entire vessel at once. As a remedy to this, the vast majority of sea cargo is arranged through freight forwarders, and is negotiated based on the POL/POD, consignment size, type and special handling needs. Shippers sending any goods via sea should liaise with their forwarders to identify the correct modality of moving their cargo from one place to another.

In sea shipping, there are heavily trafficked and well-known routes that many vessels use known as “shipping lanes,” especially between high volume ports. Between these shipping lanes, there are also what is known as “shipping lines,” or fleets of shipping vessels privately owned and managed by a company or a consortium. In addition to shipping lines, there are also a variety of smaller merchant fleets and individual vessels who work on contract for cargo movement.

Due to the sheer number of individual shippers that may be sending cargo on a single vessel, it’s extremely unlikely any one vessel will be departing from and arriving at the exact destination specified by the shipper. Cargo shipped via sea faring vessel will frequently use transhipment service, being  offloaded and reloaded onto two or more vessels while en route, staying in a secure port in between loadings while waiting for the correct vessel heading the correct destination. The linkages of a transhipment service are worked out by brokers and forwarders on behalf of the shipper, and shippers usually don’t get involved with routing, only becoming involved with cargo at the final destination.

Containerisation / Loose Item – The preferred method of shipping via sea is the use of containerisation units. Shipping containers, through their standardised construction, fit onto a wide variety of sea faring freight vessels. Containers are usually sealed at the POL, and as such can switch between multiple vessels and ports while en route with minimal risk of tampering or theft. Generally, shippers should seek to maximise their shipments by trying to reach a whole number of either 20 foot (TEU) or 40 foot (FEU) container or containers. Loads smaller than a full container load (FCL) might have to wait until a full container load is available, otherwise shippers might have to rely on what is known as “consolidation,” or sharing of one container with one or more other shippers. Less than container load (LCL) cargo using consolidation might require waiting to find another shipper or shippers going to the same final destination as you. Consolidation also does not allow for fully unopened containers to be delivered to a consignee’s facility as the cargo will need to be broken down and separated at the port, which increases the chances of loss or theft.

Special items such as generators, vehicles that cannot fit into a container, or special handling containers like refrigerated containers (reefers) may also be transhipped using two or more vessels. For oversized or bulky items, they may also be shipped by the piece, however there may be fewer available vessels with the right stowage space heading to the correct locations, which might drive up costs and slow down the entire process of shipping.

Dedicated Charters – Occasionally an agency or organisation will need to take full possession of a vessel for a single voyage or for an extended period of time. These vessel specific charters are governed by a contracting structure known as a “charterparty.” In a charterparty arrangement, the ship owner provides the vessel as a dedicated resource along with crew, and usually provides for the cost of fuel and maintenance, though the specifics of the arrangement are identified in the contract. Examples of dedicated charters in humanitarian aid might include:

• Leasing an entire bulk carrier vessel for the movement of loose grain from one location to another
• Long term leasing a cargo vessel to provide regular cargo service to locations not serviced by the commercial market
• Long term leasing of passenger vessels for special purposes (hospital boats, rescue boats, etc)