Introduction

This document summarises the Round 1 - Initial estimates of the Fine Scale Metrics for ACT Urban Habitat and Connectivity Project expert elicitation for amphibians using the IDEA protocol (refer to Hemming et al. 2018 “A practical guide to structured expert elicitation using the IDEA protocol” and Burgman 2016 “Trusting Judgements: How to get the best out of experts”).

For each question asked in the expert elicitation, we have summarised the results. All responses from the expert elicitation remain anonymous, with visualised experts estimates being denoted by a number on the x- axis. Below each visualised estimate, the comments provided by experts are collated.

The intervals displayed are for a Three-Step Elicitation.

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Structural habitat metrics

The next series of visualisations relate to structural habitat metrics.

Structural habitat metrics describe the finer scale structural elements of a species’ habitat and how the various features are arranged in space. For example, some species may need access to bare ground for nesting to be able to successfully occupy a habitat patch. This would be a structural requirement.

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Preferred % cover of rocks

Access to rocky substrate may relate to things such as habitat refugia, basking sites for reptiles, or food resources (for aquatic species). What percentage cover of rocky substrate is required for an area to be preferred habitat for this taxon group?

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 10 0 100 frogs seem to prefer rocky areas over bark chips, for refuge however if there are no rocks other structural elements could take up similar habitat functions, e.g. fallen logs etc. In Hoefer and Starrs (2016) we found Limnodynastes dumerilii was positively related to rocks in the riparian zone 50 Amphibians percent_rocks Initial
8 40 10 40 Depends on the species - some rock definitely preferred. 40 Amphibians percent_rocks Initial
26 20 10 80 the frog species considered can often be found under rocks and rock appear to provide refuge sites, but notwithstanding, they seems to also occur in areas without rocks 80 Amphibians percent_rocks Initial
27 10 0 50 This is tricky - the Litoria lesueurii and L. latopalmata are rock-dwelling specialists, whereas the common species in the urban environment are not. My response excludes these riverine specialists. 50 Amphibians percent_rocks Initial
28 20 10 35 Would depend on the species. Stony Creek frogs would have a stronger preference for more large rocks than some of the lentic species. 50 Amphibians percent_rocks Initial
Aggregated 20 6 61 NA 54 Amphibians percent_rocks Aggregated

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Preferred % cover of bare ground

Access to bare ground may relate to things such as nesting sites (for burrowing or fossorial species) or spaces to hunt. What percentage of ground needs to be bare ground for an area to be preferred habitat for this taxon group?

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 0 0.0 0 Bare ground is detrimental to frogs, not advantages 50 Amphibians percent_ground Initial
8 50 20.0 70 Heterogeneity preferable. 40 Amphibians percent_ground Initial
26 3 0.0 20 bare ground is not something i think is crucial for frogs, although if water levels are low, frogs are often found on bare ground at night 80 Amphibians percent_ground Initial
27 10 0.0 50 Large areas of bare ground may expose frogs to high levels of predation, and exposure to desiccation. While many can and do move through open exposed areas, particularly when wet, its not great habitat. 50 Amphibians percent_ground Initial
28 25 1.0 50 grass, rocks, logs, all good for frog refuge. I don’t think they require any bare ground. 50 Amphibians percent_ground Initial
Aggregated 18 4.2 38 NA 54 Amphibians percent_ground Aggregated

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Preferred % cover of grass thatch (dead, unattached grass)

Grass thatch is the layer of dead plant material that develops between the zone of green vegetation and the soil surface. We consider dead grass to be thatch once it is no longer attached to the parent plant. Grass thatch can be beneficial for some species (e.g. providing habitat for nesting) but detrimental for other species (e.g. obstructing movement). What percentage cover of grass thatch is consistent with an area being preferred habitat for this taxon group?

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 15 10 30 Grass thatch would be beneficial for frogs by providing refuge and moisture 20 Amphibians percent_thatch Initial
8 50 10 80 Depends on the density of the thatching - can be useful refuge. 20 Amphibians percent_thatch Initial
26 70 5 100 grass thatch is not directly crucial for these frogs, but can help create moist conditions favourable to them and can sometimes provide shelter sites 80 Amphibians percent_thatch Initial
27 25 0 75 Have noted in the past that many frogs will call from thatch under tussocks etc near the waters edge. Digging for Crinia spp. under Poa lab with dense thatch can often yield large numbers of frogs in swampy areas. Seems to be good habitat for some species at least. 25 Amphibians percent_thatch Initial
28 0 0 0 . 50 Amphibians percent_thatch Initial
Aggregated 32 5 57 NA 39 Amphibians percent_thatch Aggregated

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Preferred depth of grass thatch (cm)

The definition of grass thatch here is consistent with the previous question, however this question focuses on the depth of the grass thatch layer. What depth of grass thatch is consistent with preferred habitat for this taxon group? Consider the most appropriate depth of grass thatch in centimetres.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 2.0 1.0 10 no idea 1 Amphibians thatch_depth Initial
8 30.0 10.0 40 Dependent on amphibian species, and composition of grass/thatching. 10 Amphibians thatch_depth Initial
26 5.0 1.0 10 anecdotal observations suggest that areas with really thick thatch and living grass can impede the movement of frogs 80 Amphibians thatch_depth Initial
27 2.0 0.0 5 Not sure about depth - if its densely packed it might not be so good, but a couple of cm into which they can burrow is sufficient. 10 Amphibians thatch_depth Initial
28 0.0 0.0 0 . 50 Amphibians thatch_depth Initial
Aggregated 7.8 2.4 13 NA 30 Amphibians thatch_depth Aggregated

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Preferred % cover of leaf litter

Some species require access to leaf litter for food resources (e.g. arthropods and other invertebrate living in the leaf litter) or may require leaf litter as habitat refugia (for burrowing or fossorial species). What percentage of cover of leaf litter is consistent with preferred habitat for this taxon group?

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 20 10 40 talking about the terrestrial habitat only , not as overall percentage of terrestrial and aquatic habitat combined 5 Amphibians percent_litter Initial
8 15 5 50 I’m not aware of a lot of literature on LL in situ, however, some lab studies have found mixed results depending on the type of LL 20 Amphibians percent_litter Initial
26 50 20 90 leaf litter can provide important refuge sites for frogs 80 Amphibians percent_litter Initial
27 25 0 100 Depends on the species. I don’t associate many of the crinia as being heavily associated with leaf litter, but Lim. peronii on occasions (particularly on the south coast). Diversity of structural types probably of benefit from a biodiversity perspective. 25 Amphibians percent_litter Initial
28 30 20 40 some species seek refuge in leaf litter and some burrow into the soil which would be improved by that top layer. 40 Amphibians percent_litter Initial
Aggregated 28 11 64 NA 34 Amphibians percent_litter Aggregated

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Preferred % grass cover (all grasses)

The percentage cover of grass might be important for some species based on refugia sites or food resources. What percentage of grass cover is consistent with preferred habitat for this taxon group?

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 40 30 80 mowing has been shown to negatively influence the presence of some frog species 10 Amphibians percent_grass Initial
8 50 20 80 Good for refuge and may also be useful for attracting food. 20 Amphibians percent_grass Initial
26 75 40 90 no comment 80 Amphibians percent_grass Initial
27 50 0 100 Grass makes good froggy habitat. Crinia, and Lim tas love it. 50 Amphibians percent_grass Initial
28 25 20 50 depends on the species. some Crinia and Uperoleia sp most likely require more grass cover 30 Amphibians percent_grass Initial
Aggregated 48 22 80 NA 38 Amphibians percent_grass Aggregated

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Preferred total length of coarse woody debris (>10cm diameter incl. snags, stumps)

Coarse woody debris (CWD) refers to fallen dead trees and the remains of large branches on the ground in forests, grasslands and in aquatic ecosystems. Here we define CWD as being greater than 10 cm in diameter and including snags (aquatic) and tree stumps. CWD provides structure and refugia within a terrestrial habitat and changes physical and hydraulic properties in aquatic systems. CWD needs to be considered when managing forests for biodiversity but also for managing fire risk. What is the preferred total length of coarse woody debris required in an area to be preferred habitat for this taxon group? Consider the total length in metres in a one-hectare patch.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 200 100 5000 our study found that Species richness was significantly influenced by the presence of fallen logs in the riparian zone, The presence of fallen logs in the riparian zone is expected to increase the number of species present by almost 2 species 1 Amphibians cwd_length Initial
8 3 1 10 Good for refuge and attracting food. May be more beneficial for tree species. 10 Amphibians cwd_length Initial
26 150 30 250

note, I found it hard to think about what total meters would equate to in terms of frequency of CWD over a 1 ha patch. an example of total m of CWD found in a typical local woodland might be useful

frogs do occur in areas with no CWD, but where it does occur, they seem to favour it for retreat sites, so my estimates focus a lot of the ‘preferred’ element of the question 		50 Amphibians cwd_length Initial
27 500 0 5000

Not familiar with what this looks like in a 1 Ha area (usually measure CWD along a transect, rather than an area).

Either way, Large Woody debris is good habitat for many of the species. Particularly native timber. 		10 Amphibians cwd_length Initial
28 25 15 35 necessary for refuge as well as providing access to emerging froglets and basking spots. 50 Amphibians cwd_length Initial
Aggregated 176 29 2059 NA 24 Amphibians cwd_length Aggregated

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Preferred % tree canopy cover (per ha)

The tree canopy provides structure (such as shade), habitat and resources for a range of species. Tree canopy cover may influence how a species can move from one tree to the next without going along the ground, or some other feature of the taxon groups’ general biology or life history. This metric accounts for the availability of canopy cover from exotic and native tree species in the environment, as well as both young and mature trees (> 3m height). Consider the percentage cover across one hectare patch.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 25 20 50 trees are important to provide coarse wooden debris and shade (lower evaporation) and a cooler and more moist micro climate, plus refuge for tree frogs 20 Amphibians percent_canopy Initial
8 50 40 80 Important defence against desiccation and potentially predation. 50 Amphibians percent_canopy Initial
26 50 5 95 the species considered are able to use areas that are almost treeless to fully treed 80 Amphibians percent_canopy Initial
27 25 0 100

Varies between species. Some thrive in grassland environments without any tree cover, whereas others do well in forests. Solar access is an issue, so 100% canopy cover not ideal.

Maximum diversity of frogs seems to occur in open woodland, so a sparse/moderate canopy cover is good. 		25 Amphibians percent_canopy Initial
28 50 25 75 Important for shading frogs and water, providing leaf litter and refuge for some species. 50 Amphibians percent_canopy Initial
Aggregated 40 18 80 NA 45 Amphibians percent_canopy Aggregated

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Preferred % cover of below surface vegetation (aquatic only)

This could be related to the amount of food resources the species group prefers or is tolerant of in its preferred habitat, the distance an aquatic species can move from one below surface vegetation patch to the next without being exposed to predators, or some other feature of the species groups’ general biology or life history. This metric considers the availability of both exotic and native below surface vegetation species in the aquatic environment.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 25 20 70 below the surface veg provides attachment options for frog spawn of some species, food for taddies, refuge areas for taddies esp in presence of gambusia, plus important micro climates as the water around the plants is often warmer and tadpoles rest on the plants to “bask”while eating the algae growing on the plant surface or dead plant parts. 10 Amphibians percent_below_veg Initial
8 60 20 80 Important for breeding (egg deposition), refuge and as a source of food (especially tadpoles) 50 Amphibians percent_below_veg Initial
26 50 10 70 these estimates are for tadpoles 80 Amphibians percent_below_veg Initial
27 50 10 100 Some species attach eggs to submerged vegetation. Also provides habitat and food source for tadpawls. However some solar access to water is important so 100% veg cover probably not ideal. 25 Amphibians percent_below_veg Initial
28 55 40 75 important for refuge and food source for tadpoles and for attaching eggs 50 Amphibians percent_below_veg Initial
Aggregated 48 20 79 NA 43 Amphibians percent_below_veg Aggregated

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Preferred shape of bank and complexity

Streambank profiles affects stream temperature, water velocity, sediment input, refugia/cover and suitable habitat for fish. Because streambank complexity and the quality of habitat are closely linked, any change, such as erosion, can have large biological implications. This metric considers the shape and complexity of the streambank. This is measured as rugosity, the measure of small-scale variations of amplitude in the height of a surface. Rugosity can range from 0.01, a smooth, flat bank or concrete channel with no obstructions, to 0.10 in streams with large amounts of large woody debris and vegetation that impedes flow. What is the preferred bank shape for this taxon group?

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 0.00 0.00 0.00 i do not understand the metric 1 Amphibians bank_shape Initial
8 0.05 0.02 0.10 I’m not really sure about the upper limit but “a smooth, flat bank or concrete channel with no obstructions” is not ideal when taking into consideration refugia. 5 Amphibians bank_shape Initial
26 0.00 0.00 0.00 not considered for frogs 1 Amphibians bank_shape Initial
27 0.05 0.01 0.10 Stream bank complexity is good - creates habitat for frogs/metamorphs to use. Flow velocity mitigation is also valuable. Some species have more preferences for steep drop-offs with burrows/fissures for nesting (eg. Lim dumerilii). 10 Amphibians bank_shape Initial
28 0.07 0.03 0.10 helpful for refuge and providing access to waterway 50 Amphibians bank_shape Initial
Aggregated 0.03 0.01 0.06 NA 13 Amphibians bank_shape Aggregated

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Preferred slope of bank

Streambank profiles affect stream temperature, water velocity, sediment input, refugia/cover and suitable habitat and passage for aquatic and riparian species. Because streambank condition and the quality of habitat are closely linked, any change, such as erosion, can have large biological implications. This metric considers the angle of the streambank (artificial or natural substrate). What is a tolerable slope of bank to best support habitat structure and function for this taxon group? (e.g. allowing movement between the aquatic and riparian habitat, or supporting stream structure and function for small freshwater fish?) This expressed as the angle of the bank. What is the preferred bank angle for this taxon group?

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 25 3.0 90 a range of slopes is most important as different species prefer different slope angles. a uniform approach for the entire waterbody would only support a small number of species. generally waterways/bodies have a mixture of shallow and deeper edges, depending on flow direction and wind conditions etc. 25 Amphibians bank_slope Initial
8 10 0.0 40 Too high a slope (depending on the width of the bank) will impede movement. 10 Amphibians bank_slope Initial
26 0 0.0 0 not considered for frogs 1 Amphibians bank_slope Initial
27 20 0.0 90 Shallow water is generally preferred, as deep water doesn’t provide good characteristics for egg laying, tadpoles, or submerged or emergent vegetation. The exception being: Lim dumerlii like steep banks with burrows for nesting. 20 Amphibians bank_slope Initial
28 35 10.0 50 would depend on your rugosity as to how steep a bank they could tolerate. ie more logs would assist access on steep banks. 50 Amphibians bank_slope Initial
Aggregated 18 2.6 54 NA 21 Amphibians bank_slope Aggregated

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Physical chemical properties

The next series of visualisations relate to physical chemical properties.

Physical chemical properties mostly relate to the aquatic environments or soil.

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Preferred soil moisture content

Soil moisture content is the total amount of water, including the water vapor, in the soil. Soil moisture influences the vegetation species present and can affect burrowing and feeding activity of some fauna. This metric seeks to determine the preferred soil moisture content for the taxon group.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 50 20 100 sorry no idea about this metric- it is definitely not static and will change throughout each season. there would be a minimum soil moisture content for burrowing frogs to survive - as their reproduction is triggered by a strong increase of soil moisture after heavy rainfalls. 1 Amphibians soil_moisture Initial
8 50 10 90 I honestly don’t know. 5 Amphibians soil_moisture Initial
26 80 10 95 some of the species considered are burrowers and will generally prefer higher levels of soil moisture 80 Amphibians soil_moisture Initial
27 50 25 100 Not sure about this. But froggies get crispy if dry for too long. While many can aestivate(?) during dry periods, they aren’t thriving. 10 Amphibians soil_moisture Initial
28 50 30 75 important for burrowing frogs who need to maintain some moisture while buried and to be able to dig in or out 30 Amphibians soil_moisture Initial
Aggregated 56 19 92 NA 25 Amphibians soil_moisture Aggregated

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Preferred electrical conductivity (aquatic only)

Electrical conductivity is a measurement of the total combined salts/minerals in water and is used as a proxy for salinity. This metric seeks to determine the preferred electrical conductivity for the taxon group.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 0 0 0 no idea about the scale of this metric The likelihood of detecting Uperoleia laevigata dropped from approximately 80% to ~10% once the average electrical conductivity of 180 µS cm-2 had been reached 1 Amphibians elec_cond Initial
8 20 10 50 I don’t know a lot about EC but some studies have found higher occupancy with higher EC. 5 Amphibians elec_cond Initial
26 1 1 1 NOTE: i am not aware of tolerable values for amphibians - hence my values should be ignored. There is likely to be literature on this topic. I am not aware of instances of high or low salinity limiting frogs in the ACT 1 Amphibians elec_cond Initial
27 200 25 5000 ACT region generally low EC (50 - 500 uS/cm). Really polluted urban waterways get to ~ 1500 us/cm, and some natural waterways with salty geologies are getting up to 2500. Doesn’t seem to impact on them greatly with the exception of U laevigata, which seems to be sensitive to EC in an urban context at least (Hoefer and Starrs 2016). More work needed to determine if the riverine specialists (leseurii and latopalmata) are sensitive. Interactions with cytrid may change this interpretation - suggesting higher EC may be beneficial to cytrid sensitive species. 50 Amphibians elec_cond Initial
28 150 50 250 Frogwatch/Waterwatch report saw Uperoleia dropping out with EC >180ms/cm. That said, lots of other species in urban landscape handling >300. 50 Amphibians elec_cond Initial
Aggregated 74 17 1060 NA 21 Amphibians elec_cond Aggregated

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Preferred pH level (alkalinity; aquatic only)

A measure of the acidity or basicity (alkalinity). This metric seeks to determine the preferred pH level for the taxon group. The range goes from 0 to 14, with 7 being neutral. pH of less than 7 indicates acidity, whereas a pH of greater than 7 indicates a base. The pH of water is a very important measurement concerning water quality.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 0.0 0.0 0.0 0 1 Amphibians pH_level Initial
8 7.0 6.0 8.0 Ranges between 6-8. 10 Amphibians pH_level Initial
26 7.0 4.0 9.0 pH values in the range of 5 to 9 are generally what we see for farm dams in the south west slopes region and these dams support frogs 80 Amphibians pH_level Initial
27 7.0 5.0 8.0 Not sure about this at all. pH tends to range between 6 and 9, but most of the time around 7 - 7.5. Not sure how responsive frogs are, or even tadpawls. 1 Amphibians pH_level Initial
28 7.0 5.5 8.5 pH pretty stable in this catchment, so hard to know. 50 Amphibians pH_level Initial
Aggregated 5.6 4.1 6.7 NA 28 Amphibians pH_level Aggregated

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Preferred siltation levels

Siltation is water pollution caused by particulate terrestrial clastic material, with a particle size dominated by silt or clay. It refers both to the increased concentration of suspended sediments and to the increased accumulation (temporary or permanent) of fine sediments on stream or waterbody bottoms where they smother instream vegetation and cobbling occurs. Siltation is most often caused by soil erosion or sediment spill. This metric seeks to determine the maximum tolerable siltation for the taxon group within suitable habitat.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 10 0 20 really have no idea about this but had to enter numbers so here we go 1 Amphibians max_siltation Initial
8 20 0 50 Depends on the species. 5 Amphibians max_siltation Initial
26 0 0 0 not relevant for the species considered. it is relevant for some stream breeding frogs like the Booroolong Frog, but not generalists considered here 1 Amphibians max_siltation Initial
27 10 0 100 Some siltation is good for productivity but I don’t know that any frogs directly prefer it. In a terrestrial sense it smothers habitat. so not ideal. 25 Amphibians max_siltation Initial
28 30 10 50 . 30 Amphibians max_siltation Initial
Aggregated 14 2 44 NA 12 Amphibians max_siltation Aggregated

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Preferred tolerable turbidity

Turbidity is the degree of suspended solids in water that gives it a muddy colour. High concentrations of particulate matter affect light penetration, ecological productivity and habitat quality. This metric seeks to determine the preferred level of turbidity for the taxon group.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 100 10.0 500 https://camblab.info/turbidity-standards-quick-reference-guide/ turbit water has lower levels of macroinvertebrates, less plant life and is generally cooler -no good for taddies 20 Amphibians max_turbidity Initial
8 40 10.0 80 I’m not entirely sure a number of studies have found mixed results. 5 Amphibians max_turbidity Initial
26 1 1.0 1 I am not familiar with the unit of measurement. Highly turbid water is avoided by frogs 1 Amphibians max_turbidity Initial
27 10 0.0 100 Sustained turbidity bad for instream processes such as vegetation growth, light penetration etc. As such, frogs will do better in low-turbidity environments. Some seem more tolerable - eg. Lim peronii seem to exist in some questionable water quality, provided dense emergent veg is present. 50 Amphibians max_turbidity Initial
28 20 0.0 35 Consistently turbid water effect light penetration which can have adverse impacts on macrophytes. Turbidity also often carries P which promote excess algae and decreases visibility 50 Amphibians max_turbidity Initial
Aggregated 34 4.2 143 NA 25 Amphibians max_turbidity Aggregated

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Preferred dissolved oxygen concentration

The amount of oxygen present within water, either presented as an absolute amount (mg/L) or as a percentage of the total oxygen saturation at a given temperature

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 0.0 0.0 0.0 same as previous questions 1 Amphibians dissolved_oxygen Initial
8 0.5 0.2 0.7 Depends on a lot of variables. 10 Amphibians dissolved_oxygen Initial
26 15.0 5.0 18.0 drawing on DO levels in farm dams from some work we have been doing on farm dams. I’m not sure how much higher than 18 mg/L is preferable. this is about where our values max out 60 Amphibians dissolved_oxygen Initial
27 10.0 1.0 14.0 Some tadpoles seem to be reasonably tolerant of poor water quality conditions, but not necessarily for long periods. Low DO often occurs when ponds are drying out and have become stagnant. 50 Amphibians dissolved_oxygen Initial
28 85.0 75.0 100.0 important in every life stage. 50 Amphibians dissolved_oxygen Initial
Aggregated 22.1 16.2 26.5 NA 34 Amphibians dissolved_oxygen Aggregated

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Ammonia

When ammonia is present in water at high enough levels, it is difficult for aquatic organisms to sufficiently excrete the toxicant, leading to toxic buildup in internal tissues and blood, and potentially death. This metric seeks to determine the maximum tolerable ammonia levels for the taxon group within suitable habitat

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 0.0 0.0 0.0 same as before 1.0 Amphibians ammonia Initial
8 0.0 0.0 1.2 mg/L 5.0 Amphibians ammonia Initial
26 1.0 1.0 1.0 NOTE: ignore my values. I do not know about ammonia tolerance of amphibians 1.0 Amphibians ammonia Initial
27 0.0 0.0 10.0

Ammonia is tricky - its toxicity is a function of pH.

Generally ammonia shouldn’t be detectable in natural waterways without anthropogenic inputs - should be rapidly converted to nitrite - nitrate by biological processes.

I don’t know specifically if frogs or taddies are sensitive to ammonia. 		1.0 Amphibians ammonia Initial
28 1.0 0.5 2.0 Am providing nitrate estimates here as Waterwatch doesn’t measure ammonia. 10.0 Amphibians ammonia Initial
Aggregated 0.4 0.3 2.8 NA 3.6 Amphibians ammonia Aggregated

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Preferred water velocity

Water velocity relates to the speed at which water flows through aquatic habitats. This metric might influence suitability of habitat for breeding or foraging behaviour for fish and other aquatic species. What is the preferred water velocity for the taxon group within suitable habitat?

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 0 0 1.0 frogs in urban Canberra prefer still water bodies, such as ponds and dams. High flows are not tolerated as neither the tadpoles are adapted to them nor the adult frogs 25 Amphibians water_velocity Initial
8 0 0 0.0 Not aware of it being important. 5 Amphibians water_velocity Initial
26 0 0 1.0 the species considered generally like still water. I don’t appear to be able to put a value of 0.5m/s. this would be my best estimate 80 Amphibians water_velocity Initial
27 0 0 25.0 Most local species seem to prefer still water. Note: While it says units are m/s, given that decimal values are not permitted, Ive translated it to be cm/s. 25 Amphibians water_velocity Initial
28 0 0 0.0 Am not sure what the measurement would represent? I would think provided they’re not in constant flood mode (ie downstream of a hydropower dam) , they should be adapted to handling variable flow. 1 Amphibians water_velocity Initial
Aggregated 0 0 5.4 NA 27 Amphibians water_velocity Aggregated

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Preferred water turbulence

This metric refers to rapid movement of water in several directions at once, like the water movement in a rapid. The turbulence at the air/water interface is where the oxygen gas exchange takes place but high turbulence may prevent species from permanently occurring in a habitat. What is the preferred water velocity for the taxon group within suitable habitat?

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 0.0 0 1.0 local frogs for still water 20.0 Amphibians water_turbulence Initial
8 0.0 0 0.0 I’m not sure and haven’t come across research in this area. 5.0 Amphibians water_turbulence Initial
26 0.0 0 0.0 not relevant for the frog species considered that generally prefer still water 1.0 Amphibians water_turbulence Initial
27 1.0 0 25.0

Struggling to remember watts/m3 values from my fishway days! Turbulence = velocity/volume. So 1 cumec with average velocity of 100cm/s will be 100W.

Generally speaking, lower turbulence will be better, but correlated with fact that they prefer still water. 		10.0 Amphibians water_turbulence Initial
28 0.0 0 0.0 Don’t think any species in the region would be directly affected by turbulence Elsewhere some Mixophyes sp lay eggs in the riffle zone which needs a gentle flow but am not aware of such needs for frogs in the ACT. 1.0 Amphibians water_turbulence Initial
Aggregated 0.2 0 5.2 NA 7.4 Amphibians water_turbulence Aggregated

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Habitat function and risk management

The next series of visualisations relate to habitat function and risk management.

This section asks questions regarding habitat function and risk management for your selected taxon group.

These metrics describe what sorts of risks need to be managed within habitat areas to retain habitat function. The responses to these questions will aid in the identification, design and restoration of habitat patches and connectivity corridors in the urban space, provide an evidence base for policy decision making, and set thresholds for management intervention.

The answers to these questions will help us to understand how far apart different patches of habitat can be whilst still being connected for a taxon group, as well as what the aspirations should be in terms of the total extent of connected habitat at the landscape or regional scale to facilitate typical dispersal patterns for the species. Below, we ask you to provide your upper, lower and best estimates for a range of metrics related to patch size and movement behaviour.

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Preferred noise levels (during active period)

Anthropomorphic noise may impact on habitat suitability for native fauna by creating disturbance or interrupting communication pathways. This metric seeks to determine the level of anthropomorphic noise preferred by the taxon group. Sources of noise might include commercial or residential areas, traffic, or other human based sources. This metric should be based on the long-term ambient noise level during the day, and exclude short-term sounds, such as cars backfiring in a parking lot. Noises such as school bells, concerts, or sirens would all contribute to the mean noise level.

Decibels: 0 threshold of human hearing, 20 quiet room, 60 busy street, 80 loud radio, 100 subway train, 110 industrial noise, 120 jet plane take-off, 130 gun shot. Remembering that decibels are described on a logarithmic scale.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 20 0 60 …. 1 Amphibians noise_level Initial
8 20 0 50 Noise will impact call success and perhaps cause habitat abandonment. 10 Amphibians noise_level Initial
26 5 0 50 see work by Kirsten Parris on the effects of human-made noise on frogs in Melbourne 80 Amphibians noise_level Initial
27 0 0 80 Don’t know too much about this, but high background noise may impair breeding. 1 Amphibians noise_level Initial
28 35 20 50 Would possibly depend on species and how often they are exposed to noise. Frog in wetlands next to a busy road still call - but maybe they’re less productive?? 50 Amphibians noise_level Initial
Aggregated 16 4 58 NA 28 Amphibians noise_level Aggregated

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Minimum tolerable fire interval

Fire can impact on habitat suitability either by influencing core habitat structural elements (such as ground and mid-storey complexity) or by causing direct mortality to individuals or populations. This metric seeks to determine the minimum tolerable fire interval (assuming low-moderate intensity burns on a patchy sub-hectare scale) before there is an impact on resident species. The assumption is that fire is applied during the active period for the species (e.g. during daylight hours on a warm day for grassland reptiles). We encourage you to leave additional notes around any additional considerations you feel are necessary to support your response.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 48.0 24.00 60.00 … 5 Amphibians fire_interval Initial
8 36.0 36.00 100.00 Depending on the combination of isolation, vegetation types and fire histories in the study region. 5 Amphibians fire_interval Initial
26 0.0 0.00 0.00 no fire is ok for these frog species, but they also seem to be reasonably tolerable of fire 1 Amphibians fire_interval Initial
27 250.0 60.00 1000.00 Excess burning will tend to change habitat structure. Build up of key structural elements (eg. CWD) impacted as well. Mortality associated with fire will also place a lower limit on TFI, hence my estimate of 60. 25 Amphibians fire_interval Initial
28 0.5 0.25 0.75 If it was a cool. gentle fire then teh usual frog refuges should be adequate but big, hot fires, maybe not. 30 Amphibians fire_interval Initial
Aggregated 66.9 24.05 232.15 NA 13 Amphibians fire_interval Aggregated

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Minimum tolerable mowing intervals

Mowing can impact on habitat suitability either by influencing core habitat structural elements (such as ground storey complexity) or by causing direct mortality to individuals or populations. This metric seeks to determine the minimum tolerable mowing interval (assuming mowing to 5cm height using a ride-on slasher) before there is an impact on resident species. The assumption is that mowing is undertaken during the active period for the species (e.g. during daylight hours on a warm day for grassland reptiles) and covers all accessible areas (i.e. leaves patches around fence posts and sign bases). It is also assumed that there are limited other ground-layer disturbance mechanisms (e.g. herbivore grazing) taking place in mown areas. We encourage you to leave additional notes around any additional considerations you feel are necessary to support your response.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 24 24.0 99 The issue in this question is that mowing is applied to the entire area- this will be detrimental for frogs as they get killed by the mowers (cut or run over) and their refuge habitat gets destructed. In addition, mowed area hold less moisture content in the soil and heat up much more than un-mowed areas. Leaving mowing buffers of 5+ meters around wetlands is desired. Hoefer and Starrs 2016 found: Given that presence of logs in the riparian zone, and evidence of lawn mowing around the wetland were strongly negatively correlated, we fitted models with mowing in place of logs in the riparian zone. For frog species richness, mowing had a strongly negative effect, reducing the expected number of frog species from just over 5 species to less than 4 species, if mowing was evident 10 Amphibians mowing_interval Initial
8 10 0.5 100 Should be mostly fine if the mowing is done as above during the day when most species are taking refuge. 5 Amphibians mowing_interval Initial
26 2 1.0 3 mowing is likely to kill frogs and mowing around wetlands is likely to cause significant mortality. close to wetlands mowing should occur outside the spring breeding season and early summer when metamorphs are dispersing 80 Amphibians mowing_interval Initial
27 120 60.0 1000 Tricky. The development of large tussocks etc dependent on no mowing. Some species tolerant of more regular mowing/slashing but good habitat elements greatly impacted by mowing. 10 Amphibians mowing_interval Initial
28 0 0.0 0 I don’t think the frequency is as important as the buffer zone. There should be areas in the riparian zone that just don’t get mowed at all. 50 Amphibians mowing_interval Initial
Aggregated 31 17.1 240 NA 31 Amphibians mowing_interval Aggregated

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Minimum tolerable drying interval

Many species depend on accessing standing water to survive or undertake a key part of their life history cycles. Some species may be able to persist without standing water for days, weeks or months, whilst others may not. This metric seeks to determine the maximum period for which a waterbody can be ‘dry’ (no standing water) before there is an impact on the taxon group.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 5.0 2.0 18 frogs have been shown to recover from fire and drought, if there are some permanent water bodies present from which the species can re-expand after favourable conditions have returned. there is some evidence that highly ephemeral wetlands may support the largest species richness as they generally have much lower numbers of predatory species, such as Gambusia. However, wet and dry cycles need to be in accordance with breeding seasons as water is needed for reproduction, e.g. having full ponds in autumn but empty ponds in spring would be no good and would support only absolute generalist species such as Crinia signifera. 20 Amphibians drying_interval Initial
8 10.0 10.0 12 Depends on species and available habitat 5 Amphibians drying_interval Initial
26 6.0 3.0 9 timing and consistency is the key thing here. ideally wetlands/ponds have water for 3+ months in spring. Drying will kill any tadpoles present. wetlands can be dry the rest of the year. Note species breed at different times of the year. Note, that in drought, waterbodies can be dry for years and frogs skip breeding 60 Amphibians drying_interval Initial
27 3.0 0.0 36 Frogs can be resilient to drying, but not ideal. Impacts on reproduction the main issue. Regular drying will be more significant (particuarly if occurs during breeding season) than episodic large drying events. 10 Amphibians drying_interval Initial
28 2.0 1.0 3 Depends on time of year it’s dry. During winter this wouldn’t matter too much (except for over-wintering tadpoles) but during warmer months you would want at least a couple of consecutive months of free-standing water. 50 Amphibians drying_interval Initial
Aggregated 5.2 3.2 16 NA 29 Amphibians drying_interval Aggregated

Maximum tolerable level of redfin presence

Redfin are a medium-sized fish (e.g. to 400mm FL) and are highly piscivorous. They will eat everything they can fit in their mouths and hence can impact on habitat suitability and function for other aquatic native species. This metric seeks to determine the maximum density of Redfin which can persist in an ecosystem ) before an impact on habitat suitability is anticipated for other resident species.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 99 99 99 no idea about the metric or the measurements used to estimate it 1 Amphibians redfin_presence Initial
8 0 0 10 I don’t know anything about electrofishing but RF would most likely be detrimental to population success. 5 Amphibians redfin_presence Initial
26 15 1 30 I am not familiar with the typical range of values that would be expected for waterbodies in the local region. Frogs occur in waterbodies with lots of redfin, but this may be greatly compromising reproductive output and these sites may be acting ecological traps. Good aquatic and fringing vegetation provides protection from fish predation for tadpoles 80 Amphibians redfin_presence Initial
27 0 0 1 Redfin are bad! Will hoover up taddies. A low density could be tolerated, but tend to become quite abundant. Exception might be Lim peronii that appear to survive in waterways with a lot of alien fish, but dependent on dense emergent veg. 10 Amphibians redfin_presence Initial
28 0 0 0 I just have no idea what a tolerable number of Redfin would look like. I would add that my understanding of Redfin is that the more complex and structured that habitat the potentially better they would fare. 1 Amphibians redfin_presence Initial
Aggregated 23 20 28 NA 19 Amphibians redfin_presence Aggregated

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Maximum tolerable level of carp presence

Carp are a large-bodied invasive fish species, best thought of as ecosystem engineers due to their impact on the structure and function of aquatic ecosystems, competition with other fish species for resources, and simplification of food webs. This metric seeks to determine the maximum density of European Carp which can persist in an ecosystem before an impact on habitat suitability is anticipated for other resident species.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 99 99 99 I am not aware of any study looking into effect of carps on frog populations, however carp would definitely eat tadpoles frogs and spawn 1 Amphibians carp_presence Initial
8 1 0 10 Depends on the species and habitat available. 5 Amphibians carp_presence Initial
26 15 1 30 generally the local frogs will prefer fish-free ponds 80 Amphibians carp_presence Initial
27 0 0 1 Carp are bad, perhaps eat eggs, tadpoles and submerged vegetation. Lim peronii may be somewhat resilient but mediated by dense vegetation. 25 Amphibians carp_presence Initial
28 0 0 0 Like with Redfin, I would struggle to give a number here. 1 Amphibians carp_presence Initial
Aggregated 23 20 28 NA 22 Amphibians carp_presence Aggregated

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Maximum tolerable level of gambusia presence

Gambusia are highly aggressive and are very strong competitors with other small bodied and juvenile fish. This metric seeks to determine the maximum number of Gambusia which can persist in an ecosystem before an impact on habitat suitability is anticipated for other resident species.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 1.0 0 20 Hoefer and Starrs 2016 : The presence of the invasive fish, Gambusia holbrooki, had a negative impact on two species of frog, and was positively correlated with the presence of another species of frog. Gambusia holbrooki have been implicated in the decline and localised extinction of multiple species in the Sydney region (e.g. Gillespie and Hero 1999, NSW National Parks and Wildlife Service 2003, Holbrook and Dorn 2016). 15 Amphibians gambusia_presence Initial
8 0.0 0 10 Gambusia are well-known predators of tadpoles, especially of smaller species. 50 Amphibians gambusia_presence Initial
26 10.0 5 30 again, not familiar with the metric and what sort of values would be expected for local wetlands. Certainly frogs occur in ponds with lots of carp 60 Amphibians gambusia_presence Initial
27 0.0 0 5 Gambos are bad too. Feisty little buggers. Well known for chomping. Lim peronii possible resilient where dense veg is present. Gambos are open-water species, not found in large numbers in dense vegetation. 10 Amphibians gambusia_presence Initial
28 0.0 0 0 The number of gambusia might not be as important as the complexity of the habitat. With more complexity also come less open water basking areas that gambusia require that may further hamper their efforts to persist in a water body. 1 Amphibians gambusia_presence Initial
Aggregated 2.2 1 13 NA 27 Amphibians gambusia_presence Aggregated

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Maximum tolerable level of oriental weather loach presence

The impacts of weather loach on small freshwater fish are not well known. Weather loach possibly carry parasites and have the potential to be egg predators for species that lay their eggs on the substrate. This metric seeks to determine the maximum number of weather loach which can persist in an ecosystem before an impact on habitat suitability is anticipated for other resident species.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 0.0 0 10 unsure about any study looking in effects of the introduced fish on frogs/tadpoles. however they would definitely present strong competition for food resources, may introduce disease and degrade habitat 10.0 Amphibians loach_presence Initial
8 0.0 0 10 I’ve not seen research on weatherloach but I think it must be noted that they’re vile 10.0 Amphibians loach_presence Initial
26 0.0 0 0 unknown for frogs 1.0 Amphibians loach_presence Initial
27 1.0 0 100 Not sure about these ones. Probably consume frog eggs, and maybe taddies. Just don’t know enough about them. 1.0 Amphibians loach_presence Initial
28 0.0 0 0 . 1.0 Amphibians loach_presence Initial
Aggregated 0.2 0 24 NA 4.6 Amphibians loach_presence Aggregated

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Maximum tolerable presence of introduced predators (incl. fox, dog, cat)

Introduced predators such as cats and foxes are a major source of extinction for native Australian fauna. Domestic dogs are also known to impact on habitat suitability for native species. This metric seeks to determine the maximum number of individual foxes, cats or dogs which can persist in an ecosystem before an impact on habitat suitability is anticipated for other resident species. The metric considers the impacts of both domestic and feral animals combined and will assume ‘individuals’ are separate based on current best practice described in the literature if individual animals cannot be identified from markings alone.

Expert Best Lower Upper Comments Confidence Taxon Variable Group2
2 1.0 0.0 5.0 … 1 Amphibians intro_predators Initial
8 0.0 0.0 3.0 May prey on adults. Shouldn’t be a huge detriment to amphibian populations with other animal groups being at higher risk of predation. 20 Amphibians intro_predators Initial
26 5.0 1.0 15.0 see this review paper: https://www.publish.csiro.au/WR/WR19182 60 Amphibians intro_predators Initial
27 0.0 0.0 1.0 Both prey on and consume frogs. Don’t know much about impacts though. 10 Amphibians intro_predators Initial
28 2.0 1.0 3.0 . 25 Amphibians intro_predators Initial
Aggregated 1.6 0.4 5.4 NA 23 Amphibians intro_predators Aggregated