Nigeria as a member state of IMO is signatory to a significant number of IMO conventions. As stated by Dakuku [3], Nigeria has ratified Forty (40) IMO conventions and the International Labour Organisation (ILO), covering maritime safety, labour and marine environment. Nineteen of the conventions have been domesticated by way of regulation, adoption or incorporation under the Merchant Shipping Act of 2007 (Dakuku, [3] ). The Nigerian Maritime Administration stated that Nigerian government is working towards domesticating other conventions and Protocols relating to safety of Navigation [3]. For security of navigation, the Nigerian Navy has the statutory responsibility to provide Coastguard services to secure the maritime domain. At international level, the Federal government of Nigeria has initiated intergovernmental partnership in regional maritime security. It should also be stated that ISPS code for example, was implemented in Nigerian ports through NIMASA, the designated authority, in order to eradicate all forms of unlawful and criminalities such as armed robbery, cargo pilferage/theft, stowaways and so on in the nation’s seaports. In spite of these commitments, anecdotal evidence confirms the prevalence of pilferage, cargo theft, illegal importation of fire-arms, and armed robbery etc. in our port terminals.

The main objective of this study is to assess the impact of maritime security regimes on port performance and level of security incidents in Nigerian ports. However, the specific objectives are to determine:

1) Significant effect of port security measures on security incidents (proxied by cargo theft/pilferage, stowaways, attack on ships, armed robbery, human trafficking, missing of containerized cargo, drug trafficking, arms and ammunition and contraband items).

2) Significant effect of port security measures on port performance.

The security of maritime domain has been a major concern to coastal states. Maritime security threats have manifested in the use of force (by non-state actors) against the territorial integrity of a state. These security threats include: acts of terrorism against shipping operations, offshore installations, piracy and sea robbery. Others include: smuggling of migrants, narcotic drugs and arms, illegal fishing, pollution of marine environment (AMSA, [4]; Bueger, [5] ) and cyber- attacks against shipping/maritime infrastructure. Policy measures put in place by national governments and international regulatory bodies to counteract maritime security threats have found its basis on Regime theory. The Regime theory supports application of both formal and informal set of rules guiding government operations in discharging its responsibilities to the society and influence of these rules on the society (Ebaye, [6] and Levy et al., [7] ). Regime theory has also facilitated achievement of sustainable cooperation among sovereign nations (Neumayer, [8] ) in resolving environmental, economic and financial issues. In the maritime sector, security regimes relate to the set of rules created and consented to by the concerned parties to establish security mechanisms that will enhance security of maritime operations and regulate operations of users of the seas within and beyond territorial boundary of a coastal state. It is significant to state that apart from ISPS code which was IMO’s security initiative, the most significant maritime security regimes were introduced by The United States Government. These include: Container Security Initiative (CSI), Customs-Trade Partnership Against Terrorism (C-TPAT), 24-hour rule and The Proliferation Security Initiative (PSI) (UNCTAD, [9] ).

Port security is an aspect of maritime security that is very essential in facilitating safe and secure maritime transport. Port security measures are employed to safeguard seaports from terrorism and other criminal activities (Marine insight, [10] ) and should be structured to provide effective and efficient landside operations, patrols of the harbours, anchorages and waterways of ports (U.S Department of Transportation, [11] ). High rate of security incidents in ports threatens operations in port and hinders effective and efficient facilitation of trade domestically and internationally. To the authors knowledge, there have not been recorded cases of terrorists attack in any of the Nigerian ports. However, cases of armed robberies have occurred in port premises. In most cases, the sea robbers allegedly came through the waterfront in an outboard engine boat and launched attacks against ships in ports. Armed robbery attacks at ports pose a serious threat to trade. Prevention of criminal’s, initial access to the ports and vessels and demonstration of consistency in responding effectively and rapidly to any security breach is the most effective countermeasure strategy that must be adopted (U.S Department of Transportation, [11] ). Port security system must therefore be designed to have an anti-terrorist component to counter the possibility of terrorist attacks against facilities and vessels within the port. It should entail active cooperation of carriers (ocean, truck and rail) and other users of the port to proactively establish anti-terrorism response capabilities (U.S Department of transportation, [11] ), with effective and efficient port security services. Thus, port security services should include the review of vulnerabilities as regards shipboard and terminal security plans and contingency response measures for both passenger and cargo trades (U.S Department of Transportation, [11] ). Smuggling is one of the security incidents impacting Nigerian ports. Vulnerability of port security has often been exploited and hence our ports used for smuggling of narcotics, arms and ammunitions and other contrabands into Nigeria. Cargo theft is noted as one of the biggest risks facing cargo owners in Nigerian ports. Theft of imported cargo during custom’s examination and clearing process in port has negatively impacted the image of the ports and caused severe losses to importers (Eromosele, [12] ).

There have been several studies on port security, maritime security and implications of security measures on the performance of ports and shipping companies. For instance, Sadovaya and Thai [13] investigated the impacts of effective security management model on the shipping companies. The data for the study were collected from shipping ship management companies and analysed using Structural Equation Modeling (SEM) Technique. The result revealed that the security model has positive impacts on the organizational performance of the shipping companies in terms of business resilience, customer performance, time market performance and security related issues. Bichou [14] applied a stepwise Malmquist Data Envelopment Analysis approach to empirically assess the impact of procedural port security regulations on operational efficiency and productivity of container ports and terminals. The analysis revealed variations in productivity change by type of security regulations adopted across terminals but a general productivity gains were recorded. Also, empirical evidence provided by Onwuegbuchunam et al., [15] revealed that compliance to the provisions of ISPS code had positive effects on operational performance of Nigerian seaports. Yeo et al., [16] used System Dynamic methodology to analyse the relationship between seaport security levels in Korean ports and container volumes. The findings showed that significant economic benefits such as increased container throughput can be achieved by maintaining lower security level (ISPS code). Yang and Wei [17] empirically assessed how container shipping sector in Taiwan was impacted by supply chain security performance. Four crucial security dimensions were identified in the study; prevention of accident and procession; facility and cargo management; management of information; and partner relationship. Using factor analysis and multiple regression analysis models, he found that information management and partner relationship had positive significant impact on safety performance while customs clearance was positively impacted by partner relationship management. Also, Yang et al., [18] in their quest for developing a generally acceptable methodology for port security assessment and risk analysis in quantitative manner used fuzzy evidential reasoning approach to facilitate port facility security assessment (PFSA). It is pertinent to note that, despite the existence of several studies on port security and shipping company performance, empirical study on the effect of port security measures on security incidents in ports is yet to be fully researched. Thus, this study will fill this gap.

Table 2 presents the socio-economic characteristics of respondents in the study. It could be seen from the table that more than 90% of the respondents in the study are males. In terms of job experience, about 60% of the respondents have been on the job for at least 10 years. Similarly a significant percentage (>70%) respondents possesses at least a Diploma certificate. The sample population comprised more of port users (cargo and ship owners, shippers, shipping & port agents) than port authority personnel. Given this distribution, it can be taken that the respondents are knowledgeable about their activities, experienced and were in a better position to have given informed response on copies of questionnaires administered to them.

Results of the descriptive analysis as depicted in Table 3 shows that manifest variables: contra-band and stowaway items represented the highest and lowest security incidents in port respectively.

Cronbach’s Alpha and Composite reliability (CR) were used in testing the reliability of the variables. All the factor loadings were above 0.6 which make them usable for this study without having to discarding any. Table 4 shows the result for reliability and validity of factor loadings. The average variance extracted for each constructs was higher than 0.5 thresholds suggested by Hamid et al., [21]. The inner VIF for the inner model/structural model for the

Source: Author own elaboration based on survey data.

Source: Author, Data Analysis.

Source: Author, data analysis.

assessment of collinearity among the constructs is 1. However, the VIF for the measurement model for this study was not considered because they are reflective indicators.

The discriminant validity is as shown in Table 5. In this table, all the factor loadings are greater than or equal to the cross loading. This comparison satisfies discriminant validity requirement.

Figure 2 depicts the path diagram of the structural equation model in which the latent exogenous variables (port security incidents) and port performance variables are predicted by endogenous variable port security measures. The latent variables were measured by sets of observed or manifest variables. The hypotheses were tested by assessing the correlations between the endogenous variable and the exogenous variables. As regard predictive power of the model for port security measures, R² adjusted values for port performance and port security incidents indicate that the model explained 92% and 95% of the variance in port security measures.

However, analysis of the hypothesized relationship between the latent endogenous variable (port security measures) and latent exogenous variables (port security incidents and port performance) is presented in detail in Table 6. The findings as shown in Table 6 revealed that significant statistical evidence exists to accept the research hypotheses. This is evident in the large t-statistic values of 208.18 and 72.551 and their corresponding p-values all significant at 1%. Therefore the stated research hypotheses are accepted.

Source: data analysis.

The F-statistic values of 9.199 and 19.748 for port performance and port security incidents respectively are considered sufficiently high and represent large effects which imply a significant contribution to the exogenous variable (port security measures).