Résumé

Le projet de recherche MAFE est une initiative de grande ampleur dont l'objectif est d'étudier les migrations entre l'Afrique subsaharienne et l'Europe. - Attention, la documentation des enquêtes MAFE est en langue anglaise. -

The MAFE project is a major research initiative focused on migration between Sub-Saharan Africa and Europe. It brings together ten European and African research centres working on international migration.

In the early XXIth Century, international migration from Sub-Saharan Africa to Europe has generated increasing public and policy attention. The flotilla of boats bringing would-be migrants to the Canary Islands, and attempts to reach Spanish territory in Ceuta and Mellila have drawn a rapid response from Europe in the form of new policy measures. Yet the scope, nature and likely development of Sub-Saharan African migration to Europe remained poorly understood, and, as a result, European polices may be ineffective. A major cause of this lack of understanding was the absence of comprehensive data on the causes of migration and circulation between Africa and Europe.

The MAFE project aimed at overcoming this lack of understanding by collecting unique data on the characteristics and behavior of migrants from Sub-Saharan countries to Europe. The key notion underpinning the project was that migration must not only be seen as a one-way flow from Africa to Europe. The argument was that return migration, circulation and transnational practices are significant and must be understood in order to design better migration policy.

The MAFE project focused on migration flows between Europe (Belgium, France, Italy, the Netherlands, Spain and the UK) and Senegal, the Democratic Republic of Congo and Ghana, which together accounted for over a quarter of all African migration to the EU at the time of the survey. In each of these "migration systems", the survey was designed to document four key areas: - Patterns of migration : *the socio-demographic characteristics of migrants, *the routes of migration from Africa to Europe, and *the patterns of return migration and circulation. - Determinants of migration: looking at departure, but also return and circulation and taking into account the whole set of possible destinations. - Migration and Development: MAFE documents some of the socio-economic changes driven by international migration, looking as often as possible at both ends of the Afro-European migration system, at the individual level. - Migrations and Families: the data collected by the MAFE project can be used to study all sorts of interactions between family formation and international migration. Although the survey was primarily designed to study international migration, it can also be used to study other phenomena, especially in Africa: domestic mobility, labor market participation, family formation, etc. Comparable data was collected in both 3 sending and 6 destination countries, i.e. in sub-Saharan Africa and in Europe. The data are longitudinal - including retrospective migration, education, work and family histories for individuals - and multi-level - (with data collected at the individual and household levels, in addition of macro-contextual data).

Please consult the official MAFE website for further details : https://mafeproject.site.ined.fr/en/

Geographic coverage

Six European countries and three African countries participated in the MAFE surveys. Data collection was carried out in both sending countries in Africa and destination countries in Europe, in order to constitute transnational samples. For MAFE DR Congo, data was collected in the Demogratic Republic of Congo (African part), and Belgium and United Kingdom (European part).

Analysis unit

Individual Household

Univers

DR CONGO Household: Households selected randomly from the updated list of households in the selected primary sampling units. Three strata were distinguished: households with return migrants, with migrants abroad, and without migrants. Individual: People aged 25-75, born in DR Congo. This lower age limit was set in order to obtain informative life histories. By not including respondents younger than 25, the resources were used more effectively. The place of birth criterion was used to exclude people who were born out of their country of origin in order to exclude second generation migrants in Europe and to increase the homogeneity of sample. All the return migrants and partners of migrants, and one randomly selected other eligible person. Return migrants were eligible if their first departure was above at 18 or over.

EUROPE In all the European countries, the surveys were conducted among males and females who were aged 25 and over at the time of the surveys, and who were 18 or over when they had left Africa for the first time for at least one year. Migrants from only DR Congo were interviewed.

Kind of data

survey data

Frequency of data collection

DR CONGO In DR Congo, the survey preparation started in March 2009. A pilot survey was organized in May-June 2009. The selection of the survey sites was done in June 2009, and the listing of the households in the selected sites started in June and ended in July 2009. Data collection started in early August, soon after the training of interviewers and the sampling of households. It lasted for about 4 months, until mid November. Like in Ghana, both the household and biographic surveys were conducted at the same time. Editing and coding was also done during the fieldwork and ended a few weeks after the fieldwork. Because of administrative problems with money transfer, data entry started a little bit later.

EUROPE In Belgium and United Kingdom, data collection was conducted in 2009-2010. Data collection lasted about five months in the UK and seven months in Belgium. Editing was done along data collection. Data entry was done between October and December 2009 in the UK, and between December 2009 and March 2010 in Belgium.

Sampling procedure

Probability: Stratified

  DR CONGO

A three-stage stratified random sample was used. At the first stage, primary sampling units (census district) were selected randomly with varying probabilities. At the second stage, households were selected randomly in each of the selected primary sampling units (PSUs). At the third stage, individuals were selected within the households. a) Selection of primary sampling units (first stage) For DR Congo, the target area was the city of Kinshasa. In this city, a sampling frame of primary sampling units was prepared. No recent census was available, so the sampling frame of the 2007 DHS was used to select neighbourhoods, and in each selected neighbourhoods, a sampling frame of streets was prepared. In DR Congo, a sample of 29 neighbourhoods (out of 324) was selected randomly with a probability proportional to size, and 3 streets were selected randomly with a probability proportional to size in each neighbourhood (87 sampling units). The sample was stratified at the first stage in DR Congo (3 strata). b) Selection of households (second stage) A listing operation was carried out in each of the selected survey sites to prepare the sampling frame of households. The listing consisted in enumerating all the households in the selected sites, and in identifying whether these households included migrants of not. In DR Congo and Ghana, three categories of households were distinguished (households with return migrants, with migrants abroad, and without migrants). 7 households were selected in each of the 3 strata (if less than 7 households were available in one or several strata, the remaining households were selected in the other stratum). The sampling rate was higher in strata of households with migrants, in order to get a sufficient sample of such households. c) Selection of individuals (third stage) In each of the selected households, one or several respondents were selected among the eligible people (people aged between 25 and 75, and born in the origin country). In DR Congo and Ghana, all the return migrants and partners of migrants currently abroad were selected. In addition, one other eligible member was randomly selected. A special tool had been designed so that the interviewers could randomly select the people during the fieldwork. Two types of questionnaires were used in the departure countries: the household questionnaire and the individual life history questionnaire. - The first questionnaire was used among a representative sample of households in the target region. - The second questionnaire was used among a sample of individuals in the selected households, targeting both return migrants and non-migrants. The household questionnaire was thus used as the sampling frame for the selection of individual respondents.

EUROPE The objective of the survey was to obtain a sample 'as representative as possible' of the African populations (Congolese, Ghanaian, Senegalese) in the destination countries (150 individuals per origin and destination country). The way the sample was constituted may vary across countries, but some common principles were respected: - The composition of the sample should be as close as possible to the population of (Congolese, Ghanaian, Senegalese) migrants in the country in terms of gender, geographic distribution, age, socio-economic category or occupation. - One exception: the sample should be gender balanced. Males and females should be equally represented in order to allow gender analyses. - Samples in origin and destination may be linked, but migrants with weak or no relationships at origin should not be excluded from the sample. - Both documented and

As of 2021, ***** Europeans resided in Ghana. The majority of them, approximately *****, lived in the Greater Accra region, which hosts the nation's capital. Moreover, a large number of people of European origin lived in the Ashanti, Western, and Central regions. Those amounted to ***, ***, and *** people, respectively. Overall in Ghana, foreign residents are spread across regions.

Résumé

Le projet de recherche MAFE est une initiative de grande ampleur dont l'objectif est d'étudier les migrations entre l'Afrique subsaharienne et l'Europe. - Attention, la documentation des enquêtes MAFE est en langue anglaise. -

The MAFE project is a major research initiative focused on migration between Sub-Saharan Africa and Europe. It brings together ten European and African research centres working on international migration.

In the early XXIth Century, international migration from Sub-Saharan Africa to Europe has generated increasing public and policy attention. The flotilla of boats bringing would-be migrants to the Canary Islands, and attempts to reach Spanish territory in Ceuta and Mellila have drawn a rapid response from Europe in the form of new policy measures. Yet the scope, nature and likely development of Sub-Saharan African migration to Europe remained poorly understood, and, as a result, European polices may be ineffective. A major cause of this lack of understanding was the absence of comprehensive data on the causes of migration and circulation between Africa and Europe.

The MAFE project aimed at overcoming this lack of understanding by collecting unique data on the characteristics and behavior of migrants from Sub-Saharan countries to Europe. The key notion underpinning the project was that migration must not only be seen as a one-way flow from Africa to Europe. The argument was that return migration, circulation and transnational practices are significant and must be understood in order to design better migration policy.

The MAFE project focused on migration flows between Europe (Belgium, France, Italy, the Netherlands, Spain and the UK) and Senegal, the Democratic Republic of Congo and Ghana, which together accounted for over a quarter of all African migration to the EU at the time of the survey. In each of these "migration systems", the survey was designed to document four key areas: - Patterns of migration : *the socio-demographic characteristics of migrants, *the routes of migration from Africa to Europe, and *the patterns of return migration and circulation. - Determinants of migration: looking at departure, but also return and circulation and taking into account the whole set of possible destinations. - Migration and Development: MAFE documents some of the socio-economic changes driven by international migration, looking as often as possible at both ends of the Afro-European migration system, at the individual level. - Migrations and Families: the data collected by the MAFE project can be used to study all sorts of interactions between family formation and international migration. Although the survey was primarily designed to study international migration, it can also be used to study other phenomena, especially in Africa: domestic mobility, labor market participation, family formation, etc. Comparable data was collected in both 3 sending and 6 destination countries, i.e. in sub-Saharan Africa and in Europe. The data are longitudinal - including retrospective migration, education, work and family histories for individuals - and multi-level - (with data collected at the individual and household levels, in addition of macro-contextual data).

Please consult the official MAFE website for further details : https://mafeproject.site.ined.fr/en/

Geographic coverage

Six European countries and three African countries participated in the MAFE surveys. Data collection was carried out in both sending countries in Africa and destination countries in Europe, in order to constitute transnational samples. For MAFE Senegal, data was collected in Senegal (African part) and France, Italy and Spain (European part).

Analysis unit

Individual Household

Univers

SENEGAL Household: Households selected randomly from the updated list of households in the selected primary sampling units. Two strata were distinguished: the households with migrants and those without migrants. Individual: People aged 25-75 at the time of the survey, born in Senegal and who have/had Senegalese citizenship. This lower age limit was set in order to obtain informative life histories. By not including respondents younger than 25, the resources were used more effectively. The place of birth criterion was used to exclude people who were born out of their country of origin in order to exclude second generation migrants in Europe and to increase the homogeneity of sample. Up to two return migrants and partners of migrants, and one randomly selected other eligible person. Return migrants were eligible if their first departure was above at 18 or over.

EUROPE In all the European countries, the surveys were conducted among males and females who were aged 25 and over at the time of the surveys, and who were 18 or over when they had left Africa for the first time for at least one year. For MAFE Senegal, only migrants from Senegal were interviewed. This was a way to reinforce the homogeneity of the sample by excluding people of the 1.5 generation who are often "passive" migrants.

In theory, surveyed individuals must be representative of the whole population with these characteristics in the departure region and in the destination countries. The sample is composed of males and females. In Europe, in spite of a gender demographic disequilibrium, the objective was to include 50% of males and 50% of females in order to allow gender analyses.

Kind of data

survey data

Frequency of data collection

SENEGAL In Senegal, data collection activities started in November 2007 (selection of survey sites in Dakar and listing of households in the selected sites). They ended in September 2008 (data entry and data cleaning). Overall, 11 months were necessary to carry out all the activities related to data collection, and fieldwork lasted a little less than 6 months. Data collection was organized in two separate stages: the household survey was first conducted, and the biographic survey started after the household survey had been completed. The data collected in the household survey was used to prepare a sampling frame of individuals for the biographic survey; quick data entry of part of the questionnaires of the household survey was thus necessary before starting data collection for the biographic survey. Although this approach had advantages, it also lengthened the data collection process. This approach was not used for surveys in Ghana and DR Congo, where both surveys were conducted simultaneously.

EUROPE In France, Italy and Spain the surveys were conducted in 2008, before the start of the EU funded project. Data collection activities lasted approximately 6 months. Note: A second round was carried in Spain in 2010. About 400 Senegalese migrants were interviewed using exactly the same questionnaire. The data will be released in the future. For more information, contact: pau.baizan@upf.edu

Sampling procedure

Probability: Stratified

  SENEGAL

A three-stage stratified random sample was used. At the first stage, primary sampling units (census district) were selected randomly with varying probabilities. At the second stage, households were selected randomly in each of the selected primary sampling units (PSUs). At the third stage, individuals were selected within the households. a) Selection of primary sampling units (first stage) In the Senegal survey, the sample was designed to be probabilistic and representative of the Dakar region, and at the same time to maximize the chance of reaching households 'affected' by international migration (rare population). The sampling frame used to select the primary sampling units was the 2002 Population Census. The census districts (CD) -which are usually used as the primary sampling units in surveys in Senegal - have an average size of 100 households in urban areas. 60 primary sampling units were randomly selected at the first stage. This number of primary sampling units allows reaching a balance between a large dispersion of households (which decreases sampling errors) and a more concentrated sample (which reduces costs). The region of Dakar was divided into 10 strata of equal size, according to the % of migrant households within each of them (in average, 11.6% of the households were 'migrants'). 6 CD's per stratum were drawn, with a probability proportional to the number of households within each CD. In other words, census districts with a large number of migrants were more likely to be selected than those with low numbers of migrants. This approach increases the number of migrants interviewed in the individual survey, while still having a probabilistic sample representative of the target area. The listing of the households in the 60 selected primary sampling units was updated in order to select the sample of households. This stage was essential because a lot of changing occurred in some large neighbourhoods of Dakar since the previous census (2002), especially in suburban areas. This counting also allowed distinguishing between households with and without migrants. b) Selection of households (second stage) The following approach was used in MAFE-Senegal: - Households were selected randomly (using systematic random sampling) from the updated list of households in the selected PSUs. Two strata were distinguished: the households with migrants and those without migrants. A maximum of 50% of households with migrants were drawn in each district. Selected households that could not be reached (absence, refusals,…) were not replaced during the fieldwork. Replacement would distort the computation of sampling weights, and could also lead to bias the sample. To take account of refusals and absences

Insects Two different populations of Prostephanus truncatus were used in the bioassays, one originated from the invaded range in Ghana, and the other from the native range in Mexico. Both populations were maintained in the Laboratory of Entomology and Agricultural Zoology (LEAZ), at the Department of Agriculture, Crop Production and Rural Environment, University of Thessaly, Greece, on whole maize kernels, at 26°C and 55% relative humidity (RH) and continuous darkness. European Maize Hybrids Three different maize hybrids (“PICO”, “HAMILTON”, and “AGN 672”) were obtained from American Genetics SA, Sindos, Greece. All hybrids were cultivated at Serres, in northern Greece according to the local farming practices. The hybrid “PICO” has a great production potential and it is adapted to multiple soil types and can produce high-weight grain. The hybrid “HAMILTON” is a dual-purpose hybrid, that has excellent early vigor and it is tolerant to fungi, and the hybrid “AGN 672” has excellent early vigor and it is also tolerant to fungi. Population Growth on Different Maize Hybrids Three different maize hybrids (PICO, Hamilton, and AGN 672) were used for experimentation. These hybrids were untreated and uninfested, and kept at ambient conditions until the beginning of the experiments. Before proceeding with the bioassays, grain moisture content (M.C.) was assessed, using a moisture meter (mini-GAC plus, Dickey-John Europe S.A.S., Colombes, France). Standardized plastic vials as in prior work (Quellhorst et al. 2023; Lampiri et al. 2022) were used here (3 cm in diameter, 8 cm in height). Vials were then filled with 20 g of one of the three maize hybrids with lids added after. The commodity was weighed with a Precisa XB3200D compact balance (Alpha Analytical Instruments, Gerakas, Greece). The upper rings of the vials were treated with Fluon (Northern Products Inc., Woonsocket, USA) to prevent insects from moving away from the grain and/or escaping. The top of each vial also had small holes punched to allow ventilation. Each vial then received 10 P. truncatus adults of mixed sex and age from one of two different strains. Two different populations of P. truncatus were used as mentioned above. The vials were placed inside incubators set at 30°C and 65% R.H. in continuous darkness. The vials were removed from the incubators after 45 d and adult progeny production was recorded. We also recorded the weight of frass, the number of insect-damaged kernels (IDK), and the total weight of the kernels within each vial. For each combination, i.e. hybrid × strain, there were n = 9 replicates.