REASONS FOR THE DECLINE OF TRANS-SAHARAN TRADE

The trade reached its climax at around AD 8th c. by 15th c, the trade had declined due to the following reasons;

Exhaustion of the salt and gold minefields as well as other like ivory. This discouraged traders from coming to West Africa.
Increased political instability in the region due to so many wars of conquest created insecurity to the traders.
The desert conditions e.g. harsh weather, dangerous insects, snakes and robbers discouraged many traders from the activity.
Invasion of the region by the almorarids and the Tuaregs increased insecurity even more along the trade routes. Hence traders discontinued their involvement.
Moroccan invasion of western Sudan in the 16th century undermined the trade.
The growth of the trans-Atlantic trade attracted some of the trans-Saharan traders thus reducing the volume of commodities that were sold.
Colonization of west and North Africa by Europeans who took over the resources hence African activities were undermined.
Invasion of North Africa by the ottoman Turks created insecurity along the caravan routes leading to decline of the trade.

Anti-slave trade pressure from the British and eventual abolition of slave trade reduced trade profits.
The establishment of commercial ports on the western African coast and the use of navigable rivers by the 16th century AD rendered caravan trade unpopular as it was slow, cumbersome and risky.