Professor Jennifer Verduin

Globally, the presence of microplastic materials in the environment is widespread, and their largest concentrations can be found in coastal ecosystems and within mid-ocean gyres. Since the inception of mass plastic product manufacturing in the middle of the twentieth century, these durable, lightweight, and inexpensive materials have been, and continue to be, extensively exploited by humans. However, the presence of large numbers of microplastics in marine ecosystems in recent years has become a serious environmental issue that has attracted widespread interest in both the scientific and the broader community at large. In particular, the ingestion and subsequent detrimental health effects on many marine species are the most noticeable and alarming impacts of microplastics. Furthermore, recent studies have also shown microplastics can accumulate, concentrate, and act as vectors for conveying toxic pollutants within the food chain. Another feature of microplastics is their ability to transport marine species from one ecosystem to another where they become threats to local indigenous marine species. Because of the serious nature of microplastic pollution, it is important to understand their impact on coastal ecosystems and ocean gyres. This chapter discusses four aspects of microplastic pollution: 1) sources of both primary and secondary microplastics; 2) their physical and chemical behavioral properties; 3) bioavailability and behavioral properties of microplastics and their interactions with marine organisms; and 4) future perspectives, which highlights key areas of research needed to elucidate the effects of microplastic pollution in the marine environment. Importantly, understanding these four aspects of microplastic pollution will assist in directing future marine pollution research and assist policymakers to develop appropriate management strategies.

The ever-increasing use of plastic materials has also led to high levels of waste entering the environment and becoming a serious pollutant. To determine and expand knowledge of microplastic pollution in the marine environment, the present case study examines South Beach sediments. South Beach is adjacent to Cockburn Sound (Western Australia) and is made up of four smaller beaches. Each of these small beaches are each separated by a groyne. The study considered the abundance and spatial distribution of microplastic fibers in the beach sediments. The analysis technique used density separation, via a new elutriation system using hyper-saline solutions, to separate microplastic fibers from sandy beach sediments. Recuperation rates of around 95% were achieved for plastic densities ranging from 0.9 to 1.3 kg m-3. Recuperation rates for plastic densities greater than 1.4 were around 84%. The overall mean microplastic fiber density for South Beach was found to be 43.3 fibers kg-1. The fibers ranged in size from 800 to 1,824 microns, and the mean size was estimated to be 1168 ± 274 microns. The novel elutriation system developed for this study was found to be ideal for routine monitoring programs.

Globally, the presence of microplastic materials in the environment is widespread, and their largest concentrations can be found in coastal ecosystems and within mid-ocean gyres. Since the inception of mass plastic product manufacturing in the middle of the twentieth century, these durable, lightweight, and inexpensive materials have been, and continue to be, extensively exploited by humans. However, the presence of large numbers of microplastics in marine ecosystems in recent years has become a serious environmental issue that has attracted widespread interest in both the scientific and the broader community at large. In particular, the ingestion and subsequent detrimental health effects on many marine species are the most noticeable and alarming impacts of microplastics. Furthermore, recent studies have also shown microplastics can accumulate, concentrate, and act as vectors for conveying toxic pollutants within the food chain. Another feature of microplastics is their ability to transport marine species from one ecosystem to another where they become threats to local indigenous marine species. Because of the serious nature of microplastic pollution, it is important to understand their impact on coastal ecosystems and ocean gyres. This chapter discusses four aspects of microplastic pollution: 1) sources of both primary and secondary microplastics; 2) their physical and chemical behavioral properties; 3) bioavailability and behavioral properties of microplastics and their interactions with marine organisms; and 4) future perspectives, which highlights key areas of research needed to elucidate the effects of microplastic pollution in the marine environment. Importantly, understanding these four aspects of microplastic pollution will assist in directing future marine pollution research and assist policymakers to develop appropriate management strategies.

This chapter provides an account of a premier wildlife tourism attraction, taking place at the Dolphin Discovery Centre (DDC), located within the regional city of Bunbury, Western Australia. The DDC currently provides the opportunity for visitors and locals to engage in a wildlife experience focused on wild Indo-Pacific Bottlenose Dolphins that are present where the shoreline meets the city. The chapter explores the history and development of the DDC and highlights that a significant wildlife tourism attraction is possible within an urban centre when appropriate recognition, tourism management, research and environmental considerations are put into place. Wildlife tourism and operations such as the DDC provide income to the community, job opportunities and an increase in tourist visitation to a city through personal and online word of mouth. Having significant wildlife tourism experiences such as those offered by the DDC are important for many reasons especially in small regional cities such as Bunbury, Western Australia.

Connectivity among populations influences resilience, genetic diversity , adaptation and speciation, so understanding this process is fundamental for conservation and management. This chapter summarises the main mechanisms of gene flow within and among seagrass meadows, and what we know about the spatial patterns of gene flow around Australia’s coastline. Today a significant body of research on the demographic and genetic connectivity of Australian seagrass meadows has developed. Most studies have focused on the genera Posidonia, Zostera, Heterozostera and Thalassia, in tropical and temperate systems across a range of habitats. These studies have shown overwhelmingly, that sexual reproduction is important for meadow persistence, as in most cases Australian seagrass meadows are genotypically diverse, with moderate to high levels of genotypic diversity. This high diversity could be generated through demographic connectivity, recruitment of individuals sourced from within a meadow, or from dispersal between meadows. Attempts to understand the relative significance of these processes are limited, highlighting a major gap in our understanding. Genetic structure is apparent across a range of spatial scales, from m’s to 100’s to 1000’s km. At local and regional scales, particularly in confined systems such as estuaries and bays, it is not necessarily the dominant oceanographic currents influencing patterns of genetic connectivity, but local eddies, winds and tides. Over larger spatial scales, isolation by distance is consistently significant, with unique genetic clusters spreading over 100s of kilometres. This indicates that regional structure occurs at the limits of long distance dispersal for the species and this is particularly evident where meadows are highly fragmented. The number of genetic studies on Australian seagrasses has increased dramatically recently; however, there are still many opportunities to improve our understanding through focusing on species with different dispersal potentials, more detailed sampling across a range of spatial and temporal scales and combining ecological and modelling approaches.

Fluid dynamics is the study of the movement of fluids. Among other things, it addresses velocity, acceleration, and the forces exerted by or upon fluids in motion (Daugherty et al.. 1985; White. 1999: Kundu and Cohen, 2002). Fluid dynamics affects every aspect of the existence of seagrasses from the smallest to the largest scale: from the nutrients they obtain to the sediment they colonize; from the pollination of their flowers to the import/export of organic matter to adjacent systems; from the light that reaches their leaves to the organisms that live in the seagrass habitats. Therefore, fluid dynamics is of major importance in seagrass biology, ecology, and ecophysiology. Unfortunately, fluid dynamics is often overlooked in seagrass systems (Koch, 2001). This chapter provides a general background in fluid dynamics and then addresses increasingly larger scales of fluid dynamic processes relevant to seagrass ecology and physiology: molecules (μm), leaves and shoots (mm to cm), seagrass canopies (m), sea- grass landscapes (100—1.000 m), and seagrasses as part of the biosphere (>1.000 m). Although gases are also fluids, this chapter is restricted to water (i.e. compressed fluids), how it flows through seagrasses, the forces it exerts on the plants, and the implications that this has for seagrass systems. Seagrasses are not only affected by water in motion, they also affect the currents, waves and turbulence of the water masses surrounding them. This capacity to alter their own environment is referred to as “ecosystem engineering” (Jones et al.. 1994, 1997; Thomas et al., 2000). Readers are also encouraged to consult a recent review by Okubo et al. (2002) for a discussion on flow in terrestrial and aquatic vegetation including freshwater plants, seagrasses, and kelp.

Seagrass environments are characterized by physical conditions, like temperature, salinity, currents, waves, turbulence, and light. This chapter provides the methods for quantifying temperature, salinity, currents, waves, and turbulence in seagrass habitats, and describes simple, yet biologically relevant techniques that can be easily applied throughout the world. It begins with the description of two simple methods of obtaining accurate temperature data in seagrass habitats, including sediments and the water column, followed by a description of how to obtain salinity data from research vessels or directly in the seagrass habitat. Temperature and salinity can be influenced by tides and, therefore, caution needs to be taken when collecting and interpreting these data. A large variety of current meters are available in the market. Their appropriateness for seagrass research is discussed and the dye tracking method is described in detail for quantification of current velocity in seagrass-colonized areas. The same technique is later applied to the quantification of turbulence in seagrass beds. Dye tracking is a simple and inexpensive technique that allows scientists around the world to make currents and turbulence an integral part of the analysis of their data.