Kenya's sole ocean research ship gets new equipment

Agriculture Cabinet Secretary Willy Bett will today launch new state-of-the-art equipment installed on board Kenya's first oceanographic survey vessel at the Port of Mombasa.

According to a statement from the Kenya Marine & Fisheries Research Institute (Kemfri), the CS will also flag off a special expedition cruise for Kenyan marine scientists and equipment manufacturers to appraise themselves on the use of the new gadgets.

RV Mtafiti has been fitted with equipment that will transform marine research in the Indian Ocean and generate information to guide the sustainable exploitation of marine resources within Kenyas' Exclusive Economic Zone (EEZ).

The ceremony will take place at the Southern Engineering Company (Seco) dockyards within the Mombasa port.

One of the devices is a Fisheries Acoustic Eco-sounder, which has the capacity to detect fish densities at depth and distribution along the Kenyan coast.

Edward Kimani, Kemfri's assistant director in charge of fisheries, said the equipment would also gather bathymetry data for the topography of the ocean up to a depth of 10km. This would replace the conventional method of fish and count with more efficiency and accuracy in collected data.

The Acoustic Doppler Current Profiler (ACDP ) measures currents speed and direction. An ADCP anchored on the seafloor can measure current speed not just at the bottom but also at equal intervals all the way up to the surface.

The instrument can also be mounted horizontally on seawalls or bridge pilings in rivers and canals to measure the current profile from shore to shore, and to the bottoms of ships to take constant current measurements as the boats move.

In very deep areas, they can be lowered on a cable from the surface.

The equipment works by transmitting "pings" of sound at a constant frequency into the water.

HIGH PITCHED

The pings are so high pitched that not even dolphins can hear them. As the sound waves travel, they ricochet off particles suspended in the moving water and reflect back to the instrument.

Due to the Doppler effect, sound waves bounced back from a particle moving away from the profiler have a slightly lowered frequency when they return. Particles moving toward the instrument send back higher frequency waves.

The difference in frequency between the waves the profiler sends out and the waves it receives is called the Doppler shift. The instrument uses this shift to calculate how fast the particle and the water around it are moving.

RV Mtafiti embarked on a maiden cruise in December 2015 with the main focus on fisheries and hydrodynamics. The second cruise - monitoring control and surveillance - took place in February 2016.

The vessel has been used for training marine scientists in scientific sampling on cruises with participants drawn from Madagascar, Reunion, Comoros, Kenya and Tanzania.