This global meta-analysis documents data from underwater visual surveys used to determine the effect of kelp bed disturbance and canopy density on the abundance and structure of fish communities. Spatial, temporal and ontogenetic variability of many key fish species was examined at various levels of kelp disturbance at sites spanning a global temperate distribution. Rocky reef habitats and fisheries management regimes of sites were also examined as covariates.

This dataset comes from the Floating Forests project (https://floatingforests.org). Floating Forests is an online citizen science project attempting to map the cover of surface-canopy forming kelps, primarily the giant kelp Macrocystis pyrifera, using Landsat data. To acquire the data, citizen scientists were given tiles of images taken from the Landsat series of satellites (https://landsat.usgs.gov/) scenes that had been manipulated to make kelp more visible. Landsat has a roughly two week repeat time for the entire globe and a 30m resolution, although given variability in weather quarterly aggregation is recommended. Each image was scene at minimum four times. If no kelp was noted, then it was retired and scored as a zero. If kelp was noted in the first four classifications, then an individual image was shown to fifteen people total. The polygons of kelp beds presented here represent consensus classifications from the platform and are tagged with minimum number of users who classified pixels in the polygons as kelp. For example, at the five user threshold, each area represents pixels where at least five users - not necessarily the same five users - said there was kelp present. This consensus classification has been shown to match very closely to expert classifications. For more information and links to outputs, see https://blog.floatingforests.org in addition to the main project site. Or go to the main project site, and start a conversation in the "talk" section of the site.

The main aim of this research program was to determine the potential for reducing the density of urchins to encourage the return of seaweeds and an improvement in urchin roe quality and quantity from remaining urchins. Tasmanian Sea Urchin Developments used two widely-separated sub-tidal experimental lease areas. One of these areas was at Meredith Point, on the east coast, and the other at Hope Island, on the south coast. Both sites had been subject to some overgrazing by urchins. At Meredith Point, the study area was divided into plots containing urchins at three densities: artificially enhanced, continually harvested and control (undisturbed). At Hope Island, controlled clearings of urchins and limpets from barrens areas were conducted. Recovery of vegetation was monitored as well as urchin roe quality and quantity. The data represented by this record was collected at Meredith Point.

A project investigating the restoration of string kelp (Macrocystis pyrifera) habitat on Tasmania's east and south coasts. Macroalgae, fish and invertebrate counts were collected as part of the project using the Edgar Barrett transect technique in the Derwent Estuary and in the Mercury Passage on the South East Tasmania. Other fish, invertebrate and macroalgal data was also collected.

Giant kelp (Macrocystis pyrifera) forests are a foundational habitat that dominates many nearshore rocky coastlines in temperate and cold-water regions worldwide. Macrocystis forests can extend as much as 40 m to the surface and form closed canopies that alter the light, current, and sedimentation environment beneath them. They play an ecosystem-structuring function and provide habitat for a diverse range of fish and invertebrate species. The coastal waters of Tasmania represent the most extensive giant kelp habitat in Australia. Dense forests have historically covered large areas of the nearshore reef habitat, but significant declines have been recorded in eastern Tasmania in recent decades. These losses are thought to be linked to environmental stressors such as extended periods of high water movement, warming sea temperatures, and nutrient depletion. Eastern Tasmania has experienced some of the most pronounced declines, leading to the 2012 listing of the giant kelp community as an ‘endangered marine community type’ under Australia’s Federal Environment Protection and Biodiversity Conservation Act. This dataset uses Landsat satellite imagery to quantifiy the spatial extent and temporal variability of giant kelp surface canopies along the Tasmanian coastline to address gaps in long-term monitoring. The data collection is divided into two components: 1) A statewide analysis that maps the extent of Macrocystis pyrifera canopies across the whole Tasmanian coastline, grouped into nine three-year bins spanning 1987–2015. This long-term dataset is intended for assessing long-term (decadal) changes at a broad spatial scale. 2) A higher temporal-resolution analysis of 24 specific sites along the Tasmanian coastline. This dataset includes canopy coverage from all cloud-free Landsat imagery captured over the period 1986-2015 to enable detailed analysis of seasonal and interannual fluctuations in kelp canopy extent and understand localised population dynamics.

The main aim of this research program was to determine the potential for reducing the density of urchins to encourage the return of seaweeds and an improvement in urchin roe quality and quantity from remaining urchins. Tasmanian Sea Urchin Developments used two widely-separated sub-tidal experimental lease areas. One of these areas was at Meredith Point, on the east coast, and the other at Hope Island, on the south coast. Both sites had been subject to some overgrazing by urchins. At Meredith Point, the study area was divided into plots containing urchins at three densities: artificially enhanced, continually harvested and control (undisturbed). At Hope Island, controlled clearings of urchins and limpets from barrens areas were conducted. Recovery of vegetation was monitored as well as urchin roe quality and quantity. The data represented by this record was collected at Hope Island, and includes results from an inital survey collected at the site before the main study commenced.