Morphology and age cohorts of Pachygrapsus marmoratus (Grapsidae) in the southern Mediterranean Sea (Published)
The aim of this work was to establish morphological traits of P. marmoratus inhabiting the rocky intertidal zone of the southern Mediterranean Sea coast. 457 P. marmoratus collected randomly from the AL-Haniyah, Al-Hamamah, and Susah sites, eastern Libya, during 2019 were used in the study. The largest carapace length (CL) and weight (WW) were 35.1cm and 31.0g, respectively, while the minimums were 8.50cm and 0.40g. The means were 24.5cm and 10.2g. The order of WW by season was: winter and spring > fall > summer; by site: Al-Haniyah > Susah > Al-Hamamah; males being heavier than females. The WW-CL relationship was WW=0.001*CL**2.817; R2=0.909. The condition factor of P. marmoratus was highest in spring and lowest in summer, highest in Al-Haniyah and Susah and lowest in Al-Hamamah, and similar for both sexes, it increased in a negative allometric manner as the crab grew. The morphometrical parameters of male P. marmoratus were higher than those of females. Most morphometrical parameters scored higher values in winter and spring, followed by fall, and summer, with Al-Haniyah and Susah parameters being higher than the Al-Hamamah ones. Temporal and spatial variations of the morphometric parameters were discussed in terms of the availability of food and prevailing environmental conditions. Regressions of females and males P. marmoratus morphometric parameters with CL were strong and positive. Bilateral dimorphism was not observed. Four-year age groups, +1 (11-12mm), +2 (16-18mm), +3 (25-26mm) and +4 (32-33mm), comprised the P. marmoratus population.
Citation: Ayiman Faraj Eisay, Hind Abdrabba Yousef, Sayed Mohamed Ali, Ramadan A. S. Ali (2022) Morphology and age cohorts of Pachygrapsus marmoratus (Grapsidae) in the southern Mediterranean Sea, International Research Journal of Natural Sciences, Vol.10, No.3, pp.14-32
Keywords: Libya., Mediterranean, Morphology, Pachygrapsus marmoratus, morphometry
Comparative Study on Morphology of Sarpa Salpa and Dentex Gibbosus (Perciformes) From the Southern Mediterranean Coast (Eastern Libya) (Published)
Eighteen Sarpa salpa and fifteen Dentex gibbous fish collected randomly from the artisanal catch of Benghazi landing site, eastern Libya (32°36′ N 20°03′ E), during fall and winter of 2019 were used in the present study. Morphogenic features, and 21 key morphometric and 6 key meristic parameters were established for each fish. S. salpa was fusiform with a terminal mouth, narrow caudal peduncle and bifurcate caudal fin. The body was silvery white at the belly side, grading into silvery black at the dorsal side, and horizontal yellow to black stripes extended from the head region to the caudal peduncle. D. gibbosus was less fusiform with large eyes and a lunate caudal peduncle, the mouth was almost terminal, and the body was silvery but slightly pinkish and lighter at the belly side. S. salpa was heavier and longer than D. gibbosus, all its morphometric parameters were significantly higher than those of D. gibbosus except for the eye diameter and the mouth gape. This trend existed even when the parameters were related to total fish length as a ratio to eliminate the effect of size. The majority of binary pairs of morphometric parameters of S. salpa, and D. gibbosus, correlated strongly and positively with each other. Morphometric parameters located within the head region were related to the head length by linear and power regressions, and parameters located outside the head region were related to total fish length by similar regressions. Almost all regressions for both fish were positive and highly significant, indicating that all the parameters increased as the fish grew. The “b” value of the power length-weight regression indicated negative allometric growth for both fish; that of S. salpa was 2.715, and that of D. gibbosus was 2.246. The differences in morphometric traits of both fish were discussed in relation to modes of feeding and swimming, camouflage, and habitat. The Fulton condition factors were 1.733 and 1.247 in order. These factors did not change significantly during fish growth. Almost all the meristic parameters did not correlate with fish length, meaning that they were conservative features and can be used to establish meristic forms. The meristic forms derived were:
D, X-XI (XI) + 14-17 (16); A, III + 13-15 (14); P, 14-16 (15); V, I + 5; LL, 70-80 (76) for S. salpa, and,
D, XI-XII (XII) + 10-11 (10); A, III + 8-9 (9); P, 14-15 (15); V, I + 5; LL, 60-65 (62) for D. gibbosus. The numbers between parenthesis are the modes.
Citation: Amnnah khalid khalleefah, Sayed Mohamed Ali and Ramadan A. S. Ali (2022) Comparative Study on Morphology of Sarpa Salpa and Dentex Gibbosus (Perciformes) From the Southern Mediterranean Coast (Eastern Libya), International Journal of Fisheries and Aquaculture Research, 8,
(1) , 1-28
Keywords: Dentex gibbosus, Mediterranean, Morphology, Sarpa salpa, meristic, morphometry
Some morphometric traits of Liza aurata (Risso, 1810) in Umm Hufayn brackish lagoon, eastern Libya Mediterranean Sea coast (Published)
Eighty Liza aurata fish were collected from the artisanal catch of Umm Hufayn lagoon, eastern Libya, during January/ February 2018 for use in the present study. Values of key morphological parameters (descriptive, morphometric, and meristic) of the fish were established, correlated with each other, and related to fish length (as an indicator of growth and age) by power and linear regressions. The mean length of the fish was 21.331cm corresponding to weight of 89.011g. The established meristic form was: D1, IV; D2, I+ 6-9 (8); A, III, 7-12 (9); P, 12-18 (15); V, I + 4-7 (5); LL, 34-54 (42), numbers between parentheses are modes of counts. Power and linear length-weight relationship were Y=0.006X3.111, R2=0.891and Y=15.89X-250.1, R2=0.824, fish growth is almost isometric; Fulton and Clark condition factors were 0.8498± 0.01486 and 0.6651± 0.01145. These factors did not correlate significantly with fish length, i.e. they did not change significantly during fish growth.
Keywords: Libya., Liza aurata, Mediterranean, Morphometric
Irregular Migration by Sea: Contemporary Incidents in the Mare Nostrum – The Transition from State-Based Action to Humanitarian-Drive Regional Controls (Published)
Irregular sea migration has proven to be a popular means of escaping violence and armed conflict. Events after the Arab Spring in 2011 caused a lot of irregular sea migration over the Mediterranean to Europe. This created serious problems and concerns. The purpose of this research is to examine the rights of irregular sea migration in international law, constraints of states in accepting these irregular migrations and propose a solution to the problem. The paper identifies that the right to life is a fundamental legal provision that irregular sea migrants have. Therefore, it is imperative for all state and non-state actors to honor this. This can best be done by viewing the sea in a regional rather than national context. This way, states can unite and share the challenges of dealing with common issues within a regional context.
Keywords: Dublin III, Human Rights, International law, Irregular, Mare Nostrum, Mediterranean, Migration
