Although growth in the horticulture sub-sector presents many opportunities for improving food and nutritional security and growing the rural economies and livelihoods of the poor populace, it faces threats from insect pests. For instance, tephritid fruit flies impact the entire horticultural sector in the countries of Western Africa, destroying 50% to 80% of fruit production [1] , and are known to cause extensive economic losses to horticultural crops throughout Africa as a whole [2] - [10] .

Sub-Saharan Africa (SSA) alone is home to 915 fruit fly species from 148 genera, out of which 400 species develop in either wild or cultivated fruits or both. They belong mainly to three genera: Ceratitis, Dacus and Trirhithrum, which cause between 25% (Ceratitis and Trirhithrum) and 62% (Dacus) damage to fruits and vegetables [11] - [14] .

Mango (Mangifera indica L.) is the most widely cultivated fruit tree in the Sahel and one of the most important tree crops in the tropics [15] . It is a highly prized exotic fruit on the European market and one of the important fruit crops grown in tropical and sub-tropical regions [16] . The damage by B. dorsalis to mango, for instance, is estimated to vary from 40% to 90% depending on the location, the cultivar and the seasons in Eastern, Central, Southern and Western Africa [17] [18] , while in Northern Africa, Medfly Ceratitis capitata (Wied.) is wreaking havoc [19] - [21] . In addition, indirect losses attributed to the quarantine restrictions imposed by importing countries to prevent the entry and establishment of fruit flies are estimated at $2 billion annually in Africa [13] . The direct and indirect damage continue to have wide-reaching socio-economic implications, including the loss of jobs, income and trade for millions of rural and urban populations involved in the horticulture value chains across Africa.

Ochou et al. [22] noted that the prospect of enhancing the farmer’s role as an independent decision maker requires a realistic assessment of their on-farm crop protection practices and an understanding of the major constraints which may inhibit efforts to improve the pest management system. Reliable information needs to be obtained to appreciate fruit producers’ practices and to assess opportunities and constraints for decision making at the farm level so that appropriate fruit fly control decision tools and tactics can be designed to meet the needs of fruit producers. It is thus, necessary to conduct surveys that can provide farmers’ alternative view point on the crop protection constraints facing them in their efforts to increase and sustain fruit and vegetable crop production [23] . There has been increasing interest in the incorporation of farmers’ indigenous knowledge into research and development programmes for finding workable solutions to agricultural problems [24] [25] . Abdullahi et al. [26] and Benjamin et al. [27] assessed the perceptions of mango farmers on the pest status and management for B. invadens in two districts within southern and northern Ghana, respectively.

In 2006, the interception of mangoes at the borders of the European Union (EU) caused a loss of around 9 million euros for exporters in the region, or more than a third of the total value of exports of that year [28] . The pressure of fruit flies on horticultural production (yields) has a negative impact on the food, health, social security of populations and the environment (due to the use of pesticides of all kinds); and on the economic security (income, exports, competitiveness) of the mango sector in particular, is very important [28] . To provide a response to the height of the scourge, the Commission of the Economic Community of West African States (ECOWAS) initiated, in November 2014, the support Project to the regional plan of fruit flies control (FFCP), with financial support from the EU and the Agence Française de Development (AFD).

In line with the action plan of ECOWAS, FFCP, and AFD, this survey study sought to assess the perception of mango farmers on the pest status and current management options for the control of this pest. The studies were undertaken in seven districts in the Northern, Southern and Western Regions of Sierra Leone. The objectives of this study were to assess the general perception of mango farmers on the pest status of fruit fly infestations and to study the management practices adopted by the farmers.

The results of the survey indicated that mango farmers were aware of fruit flies among the major pests of mango in Sierra Leone. However, with respect to the identification of fruit fly species, the majority 30 (60.0%) of farmers demonstrated poor knowledge in identifying the actual fruit fly species, especially Bactrocera invadens, Ceratitis capitata, and Ceratitis cosyra. This was quite striking. In some cases, we had to show cards with photos of fruit flies to them so they would understand what the topic was about. This is a fact that makes farmers more vulnerable to misleading management strategies. This confirms Sarango [29] ’s observation in Malaysia, where baited methyl eugenol is frequently sold in packaging illustrated with pictures of a female melon fly. This is misleading information due to the fact that attractants do not work on female flies and methyl eugenol does not work to catch Melon flies but Oriental Fruit flies. It is clear that good knowledge of the biology and behavior of the species responsible for the crop damage is required to successfully establish and perfect integrated pest control methods. This necessitated the identification of the actual fruit fly species responsible for mango damage in the orchards in Sierra Leone.

On the effect of fruit flies fruit production, the farmers who did not correctly identified actual fruit flies, were of the opinion that, their fruits were damaged by other arthropod pests associated with mangoes. On the contrary, those that correctly identified the actual fruit flies recognized the fact that, tephritid fruit flies cause severe damage to their crops with detrimental consequences on their earnings. This knowledge could have been gained as a result of curiosity on the part of the farmers trying to know the identity of the flies they see most often or through contact with agriculture extension workers. This confirms Vayssieres et al. [1] ’s observation that losses caused by fruit flies range from 12% - 50% for mangoes in Benin, depending on the season and management practices adopted. Thus, fruit flies inflict heavy losses on fruits and vegetable crops because of their phytophagous habits [30] [31] . Activities by different fruit fly species lead to these losses and vary between fruit fly species, fruit host involved and among communities. Thus, they are accorded different economic status in different farming systems in the world [17] [26] . The knowledge of the presence of the fruit fly pests is crucial in aiding the development of solutions to minimize their effect and/or farmers’ acceptance of new innovations in combating these pests. It also has an advantage of prompting farmers to collaborate with researchers in developing sustainable on-farm environmentally friendly strategies to reduce the losses caused by the pest Abdullahi et al. [26] .

Several strategies are being adopted by farmers for the control of fruit flies (including B. dorsalis, Ceratitis capitata, C. cosyra) in Sierra Leone. These strategies include the use of insecticides, which these farmers admitted, there were satisfied with, and thought that insecticides were an effective control measure. However, effectiveness of the insecticides could be explained by the exaggerated number of applications. Many farmers sprayed their fields more than five times during the growing period without following any quarantine period. Farmers also mentioned cultural control measures, primarily field sanitation. This method focuses on the destruction of all unmarketable and infested fruits and the disposal of crop residues immediately after harvesting. Although, this is a laborious exercise, it can be effective if the fruits are collected twice a week and destroyed throughout the entire growing season [32] . Finally, a combination of insecticides and cultural practices, which proved to be the most outstanding, to manage fruit flies. It was evident that farmers adopt multiple strategies to minimize the loses due to fruit flies in an IPM fashion outlined by Ekesi and Billah [33] and Obeng-Ofori [34] . However, the recommended sustainable fruit fly management strategies indicated by growers were, training fruit growers through agriculture extension agents about appropriate methods for managing fruit fly damage to mangoes, availability/subsidy for recommended inputs for controlling the pests, and improved research on appropriate crop protection innovations.

The perceptions of Sierra Leonean farmers regarding the pest status and current management options for the control of this pest were studied in seven districts in Sierra Leone. The study showed that, although farmers mistakenly identified the actual fruit flies, they are already aware of the tremendous yield and other losses that can be incurred due to the activities of the insect pest. Regarding the management of pest, most of the farmers adopted cultural control measures, like practicing prompt harvesting, collection and disposal of infested fruits, and weeding to maintain better sanitary conditions on their farms. There is the need, therefore, to carefully study how these practices are carried out by farmers and make improvements where necessary to enhance their effectiveness in fruit fly suppression.

The authors are grateful to the Ministry of Agriculture, Sierra Leone, for funding the project.