James M. Bishop

The Gulf: A young sea in decline

This review examines the substantial changes that have taken place in marine habitats and resources of the Gulf over the past decade. The habitats are especially interesting because of the naturally high levels of temperature and salinity stress they experience, which is important in a changing world climate. However, the extent of all natural habitats is changing and their condition deteriorating because of the rapid development of the region and, in some cases from severe, episodic warming episodes. Major impacts come from numerous industrial, infrastructure-based, and residential and tourism development activities, which together combine, synergistically in some cases, to cause the observed deterioration in most benthic habitats. Substantial sea bottom dredging for material and its deposition in shallow water to extend land or to form a basis for huge developments, directly removes large areas of shallow, productive habitat, though in some cases the most important effect is the accompanying sedimentation or changes to water flows and conditions. The large scale of the activities compared to the relatively shallow and small size of the water body is a particularly important issue. Important from the perspective of controlling damaging effects is the limited cross-border collaboration and even intra-country collaboration among government agencies and large projects. Along with the accumulative nature of impacts that occur, even where each project receives environmental assessment or attention, each is treated more or less alone, rarely in combination. However, their combination in such a small, biologically interacting sea exacerbates the overall deterioration. Very few similar areas exist which face such a high concentration of disturbance, and the prognosis for the Gulf continuing to provide abundant natural resources is poor.

The effects of the river diversion, Mesopotamian Marsh drainage and restoration, and river damming on the marine environment of the northwestern Arabian Gulf

This paper summarizes the results of a study, which was conducted during the period of 1996-2005. It assesses the impact of river diversion (Third River), marsh drainage, and marsh restoration on Kuwaits marine environment. The results indicated lower salinity, higher nitrate concentration, higher chlorophyll-a, and higher sedimentation in the northern waters of Kuwait influenced by the discharge of the man-made Third River and marsh drainage. Five estuarine copepod species, which occur only in the northern waters of Kuwait due to their proximity to the mouth of the river, are reported here for the first time. Lower turbidity levels were observed in the northern waters of Kuwait during 2004 and 2005 possibly influenced by the marsh restoration process. The above results indicate the close interrelationship between the upstream river environment and the northern Arabian Gulf. River-related activities in the Tigris-Euphrates Basin have transboundary impacts downstream. Assumptions on the potential effects of the upstream damming of the Tigris and Euphrates Rivers on Kuwaits marine environment are included. It is expected that recent and planned river basin modifications in Turkey, Iran and Iraq will significantly reduce river discharge, permanently remove seasonal flooding, and impact the northern Gulfs marine environment, with serious implications for fisheries.

Depth as a factor in abundance and size of juvenile penaeid shrimps in the absence of estuaries and marshes

Triweekly trawling around low tide during daylight at 1, 2, 3, and 4 m depths along north Kuwait Bays extensive intertidal mudflats from 1 April 1985 through 9 December 1986 showed the catchability ofMetapenaeus affinis (H. Milne-Edwards, 1837),M. stebbingi Nobili, 1904,Parapenaeopsis stylifera (H. Milne-Edwards, 1837), andPenaeus semisulcatus De Haan, 1844 differed significantly with depth and season. All species were significantly more catchable in 1 and 2 m depths than in 3 and 4 m depths.M. affinis showed the clearest and most consistent relationship with depth: catchability in 1 m depths was significantly greater than that in 2 m depths (24.9 vs 5.4 per 5-min tow), and catchability in 1 and 2 m depths was significantly greater than that in 3 and 4 m depths (15.2 vs 1.4 per 5-min tow).M. affinis also showed the clearest relationship of increasing size with depth. Shrimp captured in 1 m depths were significantly smaller (~ 14 mm carapace length, CL) than those captured in 2 m depths in the spring (~23 mm CL) and summer (~ 18 mm CL). In the absence of low-salinity waters and intertidal vegetation, it is believed that the edge of the advancing and receding tide over the mudflats, i.e. the shallowest waters, provides juvenile shrimp, particularlyM. affinis, protection from predation.

Use of intertidal and adjacent mudflats by juvenile penaeid shrimps during 24-h tidal cycles

Abstract Trawl tows every 3 h throughout 24-h tidal cycles at 0.6, 1.0 and 2.0 m depths along three transects sampled the extensive intertidal and immediate subtidal mudflats in north Kuwait Bay on 4–5 June and 25–26 June, 1989. Results showed catch rates of Penaeus semisulcatus De Haan, 1844, Metapenaeus affinis (H. Milne Edwards, 1837), Parapenaeopsis stylifera (H. Milne Edwards, 1837), and M. stebbingi Nobili, 1904 to differ significantly with the main effects of diel period, depth, and tide. Interactions differed depending on species. All species were 2–5 times more catchable at night than during day. The shrimp species could be partitioned into two categories: subtidal mudflat specialists included P. semisulcatus , P. stylifera and M. stebbingi , and intertidal mudflat specialists as represented by M. affinis . Common to all subtidal mudflat specialists were increased catch rates with depth and increased catches at low tide. Highest catches of subtidal mudflat specialists usually included combinations of night, 2 m depths, and low tide. In contrast, M. affinis catch rates increased significantly with decreasing depth. Results show that the subtidal mudflat specialists remain in the area of low–low tide throughout the tidal cycle, while the intertidal mudflat specialist, M. affinis , followed the tidal front as it advanced and retreated across the intertidal area. Apparent catchability varied widely depending on timing and location showing the importance of establishing sampling criteria prior to conducting a sampling programme for recruitment indices. The behaviour patterns demonstrated by the species examined here are believed to result from predator avoidance with subtidal mudflat specialists using low tide and the cover of darkness for protection, while M. affinis utilized the shallow intertidal waters on mudflats where shrimp predators were few.

Contributed Article, A review of the impacts of aquaculture and artificial waterways upon coastal ecosystems in the Gulf (Arabian/Persian) including a case study demonstrating how future management may resolve these impacts

Abstract Preliminary calculations indicate that western Gulf intertidal mud and sand flat habitats such as those found in Kuwait may contribute some 30 percent of the gross marine productivity for this state, more than double that of any other intertidal biotope. Mud flats are dominated by a microbial mat system; recent application of the stable isotope ratio technique confirms a link between mat production and commercial fish and shrimp species. These findings demonstrate the importance of intertidal productivity so that dredging and coastal reclamation represent one of the most serious impacts on the Gulf environment. In addition, Gulf fish stocks are now fully exploited and many Gulf countries are placing further stress on coastal ecosystems through the development of aquaculture. Most of these countries now have coastal management plans with zoning of areas for conservation, recreation and development and future planning prioritization should ensure sustainability of marine biodiversity, fisheries, aquaculture, aesthetic and recreational values for coastal habitats during development. Recent coastal construction projects in Qatar, Bahrain, Saudi Arabia and Kuwait demonstrate that even within development zones it is possible to mitigate impact and even expand areas of marine productivity. Key factors are multidisciplinary approaches to design, which promote good water circulation, avoid stagnation, prevent salinity rise due to evaporation and sustain water of bathing quality. It is suggested that artifically created lagoons and waterways could be managed to provide nursery areas suitable for fishery stock enhancement.

Environmental Concerns for the Future of Gulf Coral Reefs

The Gulf is located in a subtropical, hyper-arid region. It is shallow, and bordered by several wealthy states (Fig. 16.1) undergoing rapid economic growth involving substantial construction along shores and offshore regions, underpinned by its oil and gas industry, and by wealth derived from financial centres. Thriving economic activity has, over the past few decades, begun to exert significant pressure on the Gulf’s marine environment. It is changing rapidly, by developments which include construction, substantial coastline alterations, habitat loss, creation of beds of shifting or suspended sediments, and temperature and salinity changes in restricted water flows along the coast, as well as by climate warming. The Gulf suffers from a “shifting baseline syndrome” (Pauly 1995; Sheppard 1995) and it is difficult to find any meaningful baselines, not only because of ongoing, intensive constructions that cause large-scale alterations of the environment, but also because of several recent episodes of marine mortality from seawater warming.

A review of the status and development of Kuwait’s fisheries

The status of Kuwaits fisheries landings and relative abundance for major species was reviewed using research data from Kuwait Institute for Scientific Research and landing data from the Kuwaits Central Statistical Bureau. Landing data showed significant decreases for major commercial species such as zobaidy (Pampus argenteus), suboor (Tenualosa ilisha), hamoor (Epinephelus coioides), newaiby (Otolithes ruber) and hamra (Lutjanus malabaricus) while abundance data for the shrimp Penaeus semisulcatus showed significant reduction in the recent years mainly because of overfishing. The catch-rate data showed continuous decline for major species such as zobaidy, newaiby and hamoor, which indicate that stock abundances of these species are low. The reduction in stock abundance in context with changes in habitat quality, particularly the effects of reduced discharge of the Shatt Al-Arab, is discussed.

Quantitative observations on marine mammals and reptiles of Kuwait’s Boubyan Island

Abstract Quantitative observations were recorded on air breathing marine vertebrates in the immediate vicinity of Boubyan Island from 17 February 2004 through 1 March 2005. In 398 hours of observation time during daylight, we made 159 sightings of Indo-Pacific Humpback Dolphins (Sousa chinensis) for a combined total of 524 individuals. We also recorded 38 individual seasnake (Hydrophis spp.) sightings. No marine turtles were observed during the study period. Pod size of the dolphins ranged from one to at least 30. Of the 159 sightings, 40% was comprised of a single individual, and 26% consisted of pairs. Pods of 10 or more members were observed on 13 occasions. Overall, we saw an average of 1.35 Sousa for each hour of observation time. Seasonal counts peaked in the spring with nearly 2 Sousa/h, and reached 3.3/h in April. Observation rates in the winter dipped to less than 0.7 Sousa/h. Khor Abdullah had the highest overall observation rate with 2.6 Sousa/h, and in the fall, this rate jumped to 4.3/h. In comparison, Hydrophis sea snakes were few with an overall observation rate of 0.1/h. This low number reflects the fact that sea snakes are present mostly in the summer, and are far less noticeable. Seasonal observation rates peaked in the summer with nearly 0.3/h and dipped to zero during the winter months. Sea snakes initially showed up in April when water temperature was just over 21ºC, and were no longer observed in November when water temperatures dropped from >20ºC in October to about 15ºC by December. Both Sousa and Hydrophis are relatively long-lived, apex species and could serve as environmental indicators for Boubyan Island’s planned development. Monitoring population abundances and tissues for contaminants is recommended.

Field experiments to improve the efficacy of gargoor (fish trap) fishery in Kuwait’s waters

Fish traps were investigated to understand the effects of season, bait type, trap size, and trap soak time on catch rates, catch composition, and trap loss rates from March 2004 to September 2005, to improve the performance and management of Kuwait’s gargoor (cage style fish trap) fishery, which used to be the nation’s most important one in terms of value and landings volume. Catch rates were the highest in April/May (5–8 kg/trap haul) and again in December (7 kg/trap haul). Bait type and trap size also affected catch rates and species composition. Of the seven baits tested, the best catch rates, >5 kg/trap haul, occurred with cuttlefish (Sepia pharaonis), but wolf-herring (Chirocentrus dorab) and mullet (Liza klunzingeri) also produced good results (4–5 kg/trap haul). Within the five tested sizes, the two largest-sized traps captured more fish and larger size fish. Analysis of variance (ANOVA) showed significant differences of catch rate among traps with different baits as well as among traps of different sizes. Duncan test further revealed these differences between two specific baits and sizes. Cluster Analysis of species composition showed more differences among different baits than among different trap sizes. Longer soak times did not result in larger catch rates, but increased trap loss. About 10-day soak time resulted in trap loss 7%, while 40-day soak time could result in a loss of around 20%. Consequently, it is recommended that the gargoor be checked every 10 or fewer days. The average overall catch rate during the study period was lower than that of 1980s (4.5 vs. 5.8 kg/trap haul), indicating a possible decline of fish abundance in Kuwait’s waters. It is recommended that the number of gargoor fishing boats and gargoors from each boat should be limited to allow stock rehabilitation.

A quantitative and statistical biological comparison of three semi-enclosed seas: the Red Sea, the Persian (Arabian) Gulf, and the Gulf of California

Similar habitats separated by great distances can provide remarkable examples of convergent evolution in biological diversity, and have been influential in our understanding of community ecology, historical biogeography, and evolution. Here, we compare three semi-enclosed seas in arid regions of the northern hemisphere, the Red Sea, the Persian (Arabian) Gulf, and the Gulf of California, and test whether they show similar biodiversity patterns. Despite large geographic separations between the seas, the similar shapes and latitudinal locations lead to several analogous abiotic conditions. These similarities, however, do not result in equivalent biodiversity patterns, even when correcting for different regional species pools. Comparisons revealed that the Red Sea contains a greater species diversity of vertebrates, but that the Gulf of California contains the greatest species diversity of invertebrates. Notably, vertebrate abundance patterns were statistically similar between the Persian Gulf and the Gulf of California. Divergences are likely due to variable habitats within each sea, several influential abiotic differences, and dissimilar histories among the seas. While these results support a null hypothesis of biological dissimilarity despite abiotic similarities, they are the first statistical comparisons of the biotas of these three regions. Continued statistical comparisons among marine ecosystems have the potential to reveal ecological and evolutionary patterns that typically go unnoted.