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The benefits of ecosystem services to cities are well documented; for example, water-sensitive urban design to mitigate stormwater flows and purify run-off, the cooling benefits provided by tree shade, and psychological benefits of urban greening. Cities tend to displace nature, and in urban environments where nature exists it tends to be as highly altered ecosystems. This paper sets out how it is possible to regenerate nature in cities. We outline the principles of how to do this through a study on a new regenerative urban development in Perth, Australia, where urban planning is intended to support the regeneration of a bioregional habitat within the city. The authors, drawn from sustainability, property development and ecological backgrounds, describe how urban regeneration can potentially facilitate the regeneration of endemic habitat within the city. This builds on the original ecosystem functionality to provide an urban ecosystem that enables biodiversity to regenerate. Perth lies on the Swan Coastal Plain, a biodiversity hotspot; it is home to 2.1 million people and numerous endemic species such as the endangered Black Cockatoo. Low reproduction rates and habitat loss through agricultural clearing, fire and urban expansion have greatly reduced the Black Cockatoo's range and this continuing trend threatens extinction. However, the charismatic Black Cockatoos enjoy passionate support from Perth's citizens. This paper describes a range of strategies whereby new urban development could potentially harness the popularity of the iconic Black Cockatoo to build momentum for urban habitat regeneration (for the cockatoos and other species) on the Swan Coastal Plain. The strategies, if systematically operationalised through urban planning, could allow city-scale ecological gain. The authors suggest a framework for nature-positive design and development that offers multiple benefits for human and non-human urban dwellers across scales, from individual gardens, to city/reg, open access

The electrosensory system is found in all chondrichthyan fishes and is used for several biological functions, most notably prey detection. Variation in the physical parameters of a habitat type, i.e. water conductivity, may influence the morphology of the electrosensory system. Thus, the electrosensory systems of freshwater rays are considerably different from those of fully marine species; however, little research has so far examined the morphology and distribution of these systems in euryhaline elasmobranchs. The present study investigates and compares the morphology and distribution of electrosensory organs in two sympatric stingray species: the (euryhaline) estuary stingray, Dasyatis fluviorum, and the (marine) blue-spotted maskray, Neotrygon kuhlii. Both species possess a significantly higher number of ventral electrosensory pores than previously assessed elasmobranchs. This correlates with a diet consisting of benthic infaunal and epifaunal prey, where the electrosensory pore distribution patterns are likely to be a function of both ecology and phylogeny. The gross morphology of the electrosensory system in D. fluviorum is more similar to that of other marine elasmobranch species, rather than that of freshwater species. Both D. fluviorum and N. kuhlii possess 'macro-ampullae' with branching canals leading to several alveoli. The size of the pores and the length of the canals in D. fluviorum are smaller than in N. kuhlii, which is likely to be an adaptation to habitats with lower conductivity. This study indicates that the morphology of the electrosensory system in a euryhaline elasmobranch species seems very similar to that of their fully marine counterparts. However, some morphological differences are present between these two sympatric species, which are thought to be linked to their habitat type.

There is an increasing need for environmental measurement systems to further science and thereby lead to improved policies for sustainable management. Marine environments are particularly hostile and extremely difficult for deploying sensitive measurement systems. As a consequence the need for data is greatest in marine environments, particularly in the developing economies/regions. Expense is typically the most significant limiting factor in the number of measurement systems that can be deployed, although technical complexity and the consequent high level of technical skill required for deployment and servicing runs a close second. This paper describes the SmartEnvironmental Monitoring and Analysis Technologies (SEMAT) project and the present development of the SEMAT technology. SEMAT is a "smart" wireless sensor network that uses a commodity-based approach for selecting technologies most appropriate to the scientifically driven marine research and monitoring domain/field. This approach allows for significantly cheaper environmental observation systems that cover a larger geographical area and can therefore collect more representative data. We describe SEMAT's goals, which include: (1) The ability to adapt and evolve; (2) Underwater wireless communications; (3) Short-range wireless power transmission; (4) Plug and play components; (5) Minimal deployment expertise; (6) Near real-time analysis tools; and (7) Intelligent sensors. This paper illustrates how the capacity of the system has been improved over three iterations towards realising these goals. The result is an inexpensive and flexible system that is ideal for short-term deployments in shallow coastal and other aquatic environments.

The Port of Brisbane disturbance of the sedimentary environment at the mouth of the Brisbane River was assessed at the inner and outer river and in two periods following disturbance: 2 weeks (March) and 8 months (November) after dredging. Sediments in the inner river were dominated by silt, while in the outer river sediment were sandier. Total and organic carbon (TC and Corg) and total Kjeldahl nitrogen (TKN) were higher in the inner river, which could be an indication of higher organic loads. Ammonia (NH 4-N) and nitrate (NO 3-N) sediment profiles indicated suboxic conditions and denitrification in the inner river, as well as oxic conditions and nitrification at the outer river. Total meiofauna abundance and taxa composition was similar in both, the inner and outer river locations. For some individual taxa however, the suboxic sedimentary conditions in the inner river were adverse. Copepods, polychaetes and sipunculids abundance were lower in the inner river, and negatively correlated with fine sediments and high organic loads, and positively correlated with oxic conditions. Furthermore, the port strategic dredging operations had negative effects on the meiofauna of both locations. The abundance of most of the taxa in both the inner and outer river locations during March was lower at sites inside the dredged navigational channel than at the sites outside the channel. The meiofauna rapidly re-colonise the disturbed sediments as by November the abundances inside the channel considerably increased. The composition of the meiofaunal and nematode assemblage from different sites and months showed significant differences. The nematode assemblage at the mouth of the Brisbane River dominated by Sabatieria and Metalinhomoeus was characteristic of disturbed sediments.