Ballast water management in Canada: A historical perspective and implications for the future

Non-indigenous species (NIS) can create significant risks when introduced to foreign ecosystems. One of the many vectors facilitating the global transport of NIS is ballast water, and as commercial shipping increases so does the threat of ballast water-mediated introductions. Despite Canadian regulations, consistent with international guidelines put forth by the International Maritime Organization in the early 1990s, ballast water remains a potential vector for the introduction of many NIS to Canadian marine ecosystems: there have been no new introductions in the Laurentian Great Lakes Region since 2006, yet marine ecosystems continue to see the introduction and establishment of NIS. This paper details and analyzes the development of Canadian ballast water management (BWM), in the context of marine ecosystems, and identifies issues therein. BWM in Canada has a number of management gaps that have persisted since large-scale BWM began in the late 1980s. These include BWM exemptions for vessels not exiting the North American continental shelf, and limitations of effectiveness of mid-ocean exchange as the predominant management method in marine ecosystems. In addition, ballast water regulations for the Canadian Arctic may require additional consideration as the Arctic will likely continue to see an increase in both warming and commercial shipping in the future, thereby increasing the potential risk of NIS. In order to adequately protect all Canadian marine ecosystems, it is recommended that the current BWM regime: fill gaps in management to help prevent further introduction and spread of NIS; focus equally on both marine and freshwater regions, and; look to other aggressive BWM strategies such as those being developed by the state of California.     

Marine reserve establishment and on-going management costs: A case study from New Zealand

While there is considerable international research focused on the conservation outcomes of marine protected areas (MPAs) and marine reserves (MRs) there is little information on the economic cost to establish and manage these protected areas. This study estimated the MR pre-establishment and establishment costs for the Taputeranga Marine Reserve (TMR) in New Zealand (NZ) and determined the annual management costs for this reserve and four further NZ MRs. Finally, the cost to local rock lobster fishers resulting from the displaced fishing effort once the TMR had been established was estimated. This research found that the TMR pre-establishment cost was approximately NZ$508,000, and the establishment process cost was approximately NZ$353,000. The annual management costs across the five reserves ranged between NZ$43,200 and NZ$112,500 between 2008/09 and 2010/11. The annual fishers displacement cost at TMR was approximately NZ$22,000 per annum. This research showed that on a unit area basis, small MRs in NZ are just as expensive to maintain as large MRs. This study also highlighted how volunteer effort helped to considerably reduce the monetary cost of the MR pre-establishment process. This research increases our understanding of establishment and management costs, and supports future planning of MRs both within NZ and internationally.     

Flexibility in temporary fisheries closure legislation is required to maximise success

Temporary closures have been used for centuries in many parts of the world as a tool for fisheries management and restoration. The length of time that a closure is in place can play a determinative role in the effectiveness of the closure as a means of restoring stock biomass and diversity. For species that are slow growing and slow to reproduce, closures shorter than a decade are unlikely to be sufficient for the effects of restoration to accrue. New Zealand has two legislative mechanisms specifically designed to establish temporary closures: sections 186A and 186B of the Fisheries Act 1996. These provisions were created to respond to localised depletion and to provide for the use and management practices of Māori (New Zealand’s Indigenous People). There is currently a two-year time limit on temporary closures applied for by the community. By defining a time limit for temporary closures legislators have failed to account for the ecology of many of the species targeted for protection that require longer periods of protection for restoration. Furthermore, the way in which the final decision making power is vested with central government is also inconsistent with the original purpose of the provisions. An amendment to the temporary closure provisions is suggested to provide greater flexibility for users and to better recognise the non-commercial fishing rights provided for by the Fisheries Act 1996, of local communities seeking to apply this tool.     

Ice-sheet dynamics through the Quaternary on the mid-Norwegian continental margin inferred from 3D seismic data

Reconstructing the evolution of ice sheets is critical to our understanding of the global environmental system, but most detailed palaeo-glaciological reconstructions have hitherto focused on the very recent history of ice sheets. Here, we present a three-dimensional (3D) reconstruction of the changing nature of ice-sheet derived sedimentary architecture through the Quaternary Ice Age of almost 3 Ma. An extensive geophysical record documents a marine-terminating, calving Fennoscandian Ice Sheet (FIS) margin present periodically on the mid-Norwegian shelf since the beginning of the Quaternary. Spatial and temporal variability of the FIS is illustrated by the gradual development of fast-flowing ice streams and associated intensification of focused glacial erosion and sedimentation since that time. Buried subglacial landforms reveal a complex and dynamic ice sheet, with converging palaeo-ice streams and several flow-switching events that may reflect major changes in topography and basal thermal regime. Lack of major subglacial meltwater channels suggests a largely distributed drainage system beneath the marine-terminating part of the FIS. This palaeo-environmental examination of the FIS provides a useful framework for ice-sheet modelling and shows that fragmentary preservation of buried surfaces and variability of ice-sheet dynamics should be taken into account when reconstructing glacial history from spatially limited datasets.     

New style of honeycomb structures revealed on 3D seismic data indicate widespread diagenesis offshore Great South Basin,New Zealand

In the Great South Basin, within the Eocene section, at time-depths around 700–900 ms two way time below the seafloor, unusual features are observed on 3D seismic data closely associated with polygonal faults. The features, referred to as honeycomb structures (HS), cover an area of ∼600 km², are packed circular, oval, to polygonal depressions 150–400 m across in plan view and several to 10 + m in amplitude. Polygonal faults rapidly die out at the Marshall Paraconformity, which is overlain by the Oligocene Penrod Formation. Hence the polygonal faults are inferred to have formed prior to the Marshall Paraconformity, and they cross-cut HS features. Consequently the top of the HS probably formed at burial depths of around 375–500 m, which is their decompacted depth below the paraconformity. The interval containing HS is about 125 m vertical thick. There are several possible origins for the HS. The most probable is related to bulk contraction of the sediment volume accompanied by fluid expulsion, which suggests a diagenetic origin, in particular the opal-A/CT transition. There are actually two polygonal fault systems (PFS) present in the area. The Southern Tier 1 PFS lies laterally to the HS and overlaps with it. The Northern PFS (Tier 2) lies above the HS, appears to be independent of the HS, and formed in the upper 200–300 m of the sediment column. The Tier 1 PFS probably formed by shear failure related to the same diagenetic effects that caused the HS.     

New insights into the carbonate karstic fault system and reservoir formation in the Southern Tahe area of the Tarim Basin

As worldwide hydrocarbon exploration has extended from shallowly to deeply buried strata, reservoir quality has attracted substantial and persistent interest in petroleum geology. In particular, deeply buried strata (>5500 m) in the Tarim Basin have attracted considerable attention because carbonate reservoirs that have experienced fracture or dissolution have also been shown to demonstrate considerable hydrocarbon potential. Therefore, it is necessary to determine how these reservoirs are developed and distributed in detail from both scientific and practical standpoints.In this paper, we address this issue using a case study in the southern Tahe area, which is contained within the largest Palaeozoic marine oilfield in China. In the northern Tahe area, mega-paleokarst systems developed in the Ordovician strata; however, the reservoir quality in the southern part of the Tahe area is relatively poor because it is covered by insoluble formations during karstification. Observations of cores and analyses of images of well logging demonstrate that these reservoirs are dominated by caves, vugs and fractures that have developed near faults. We speculate that the faults penetrating insoluble formations represent the main dissolution passages that originally developed these karstic fault systems. Additionally, we analyse a series of outcrops, seismic data, and structures to characterize the spatial geometry of these major faults and their surrounding fractures in detail. Most of these are strike-slip faults, and their subsequent reservoirs can be divided into three categories based on their development, including dendritic, sandwich and slab reservoirs. Recent studies demonstrate that karstic fault reservoirs are most common traps in the study area. Although various types of carbonate karstic fault reservoirs are represented in this region, the dendritic karstic fault reservoir is the most hydrocarbon-rich.Guided by these initial results, 108 wells were drilled from 2013 to 2014, producing 485 thousand tons of oil and yielding success ratios greater than 89%. The average production of dendritic reservoirs is 37.4 tons per day (t/d), while those of sandwich and slab types are 20.2 t/d and 14.0 t/d, respectively. These results represent significant references for future hydrocarbon exploration and the development of similar deeply buried karstic fault reservoirs in the Tarim Basin and elsewhere.     

Sedimentary control on the formation of a multi-superimposed gas system in the development of key layers in the sequence framework

Based on core observations, well logs and test results of siderite-bearing mudstone from the Benxi Formation to the Member 2 of the Shanxi Formations in the Linxing block, northeastern Ordos Basin, a logging identification model for siderite-bearing mudstone (key layer) was established. The porosity characteristics and sealing property were quantitatively evaluated by logging data. Sedimentary control on the formation of multi-superimposed gas-bearing system in the development of key layers in the sequence framework was also discussed. The results showed that the siderite-bearing mudstone has obvious logging response characteristics, e.g., high photoelectric absorption cross-section index (PE), high density (DEN), high amplitude natural gamma ray (GR), low acoustic (AC), low resistivity (M2RX) and low neutron porosity (CNCF). The quantitatively evaluated results of the porosity characteristics and sealing property for the key layer showed that the key layer has the characteristics of low porosity (with an average of 1.20 percent), low permeability (with an average of 2.29 × 10⁻⁸μm²), and high breakthrough pressure (with an average of 12.32 MPa) in the study area. This layer acts as an impermeable gas barrier in a multi-superimposed gas system. The results also indicated that the material composition of the multi-superimposed gas-bearing system can be established by the sequence stratigraphic framework. The sedimentary evolution results in a cyclic rhythm of material composition vertically. The spatial distribution of the corresponding transgressive event layer near the maximum flooding surface (MFS) in the sequence framework restricts the spatial distribution of the key layer with high breakthrough pressure and low porosity, which constitutes the gas-bearing system boundary. The siderite-bearing mudstone formed near the MFS in the second-order sequence and constitutes a stable comparison of the first-order gas-bearing system boundary, which has a wide range of regional distribution and stable thickness. The siderite-bearing mudstone formed near the MFS in the third-order sequence is often incompletely preserved due to the late (underwater) diversion channel erosion and cutting. This layer forms the coal-bearing reservoirs, which we termed as a second-order gas-bearing system in adjacent third-order sequences to form a uniform gas-bearing system.     

Fisheries learning exchanges and sea turtle conservation: An effort between Mexico,Cuba and the U.S. to engage Cuban coastal communities in non-consumptive alternative behaviors

The purpose of this short communication is to describe the Third International Workshop on Sea Turtle Conservation and Fisheries Exchange that took place from April 22–30, 2009 on Cuba’s Isla de la Juventud [Isle of Youth]. A group of 28 fishers, conservationists, marine scientists and fisheries managers from Cuba, Mexico and the U.S. gathered at Siguanea Bay off the island’s southwest coast. The goals of the exchange were to 1) provide a forum for sea turtle experts and fishing communities in Cuba, Mexico, and the U.S. to share experiences on conservation activities, 2) develop the scientific basis for future conservation in this highly biologically important region of Cuba, and 3) increase support by Cuban fishers for local sea turtle conservation efforts. During the exchange, participants met with local Cuban fishers about the challenges of conserving sea turtle populations while maintaining their fishing livelihoods, shared solutions developed by fishers to accomplish the same in Mexico, and undertook field and cultural activities. Key outcomes for the exchange include an improved understanding of sea turtle bycatch off the Isla de la Juventud, enhanced collaboration among the three nations in turtle conservation, and increased motivation by fishers to participate in sea turtle research and conservation. Additionally, as a direct result of this exchange, the community of Cocodrilo on the Isla de la Juventud has hosted annual sea turtle festivals that increase support for turtle conservation efforts by the local community.     

ScotMap: Participatory mapping of inshore fishing activity to inform marine spatial planning in Scotland

A detailed understanding of fishing activity in Scottish waters is required to inform marine spatial planning. Larger fishing vessels are fitted with Vessel Monitoring Systems (VMS) offering spatial information on fishing activity. VMS does not cover smaller vessels (under 15 m), which fish predominantly in inshore waters where the competition for space is often greatest. To improve knowledge of the distribution of fishing activity and value of fisheries in Scotland's inshore waters, Marine Scotland conducted a participatory fisheries mapping project, known as ScotMap. The data were collected during face-to-face interviews with 1090 fishermen of Scottish registered commercial fishing vessels under 15 m in overall length and relate to fishing activity for the period 2007–2011. Interviewees were asked to identify the areas in which they fish, estimate the contribution these areas make to vessel earnings, and to provide associated information. The majority of interviews relate to creel fishing. The data collected were aggregated to provide mapped outputs of the monetary value, relative importance to fishermen and the usage of the seas around Scotland (number of fishing vessels and number of crew). ScotMap outputs provide information on the locations of inshore fishing activities and the economic importance of different sea areas at a much higher spatial resolution than was previously possible. Outputs have informed marine policy development, provide a valuable resource for marine spatial planning in Scotland and illustrate how participatory mapping can generate useful resources on the location and importance of inshore fishing areas.     

Environmental management frameworks for offshore mining: the New Zealand approach

The New Zealand region contains untapped natural mineral, oil, and gas resources while also supporting globally unique and diverse faunal communities that need to be managed sustainably. In this paper key information from the international literature is reviewed that can underpin an Environmental Mining Management System which includes elements of Environmental Risk Assessment, Environmental Impact Assessment and Environmental Management Planning. This paper focuses on four developing areas of seafloor mining activities presently being undertaken or planned in the New Zealand region: hydrocarbons (oil and gas), minerals, ironsands and phosphorite nodules. A number of issues with the implementation of environmental management systems are identified including the difficulty of assessing new marine activities or technologies and the need for standardised reporting metrics. Finally, the development of ecosystem-based management and marine spatial planning is discussed which will be required to enhance environmental mining management frameworks in New Zealand.