City Nature Challenge 2020: Greater Adelaide - Taking on the Challenge

Time

The observation period of the challenge runs over 96hrs. There are two extreme approaches that can be taken to the challenge: (1) Maximise your observations, or (2) Maximise your species. A more enjoyable approach is likely some combination of the two.

Maximising Your Observations

Upper Limits
Each year that the City Nature Challenge is run, the record for observations and species observed by a single contributor is broken. In 2019 the contributor with the highest number of observations uploaded 4,039 records across the 4 challenge days (amazingly almost all were verifiable). Assuming observations are taken only during daylight this equates to an observation every 38 seconds for 4 straight days! Even considering some of these may have been after dark, this can probably be considered a reasonable upper limit to how many observations can be taken by one individual during the challenge, although no doubt someone will eventually crack 5,000 observations.

The highest number of species observed by a single contributor was 1,014 from only 1,232 observations across the 4 days. Clearly the approaches to achieve either of these are quite different.

Even if choosing to maximise the number of observations, quality and value of observations should be considered. Thousands of observations of unidentifiable organisms or garden plants is of little real value. Take the time where necessary to ensure each observations has photos that give it the best chance to be identified down to species level.

Represented Taxa
A look at exactly what species were observed by the highest single contributor shows that over 90% were Plants. This holds true for many of the highest contributors during the challenge having at least 50% Plants (with Insects the next highest group, but primarily for Northern Hemisphere cities). So, if you goal is to maximise the number of observations you take, then find a large natural area with a high density of under-story plants. Repeated observations of the same species is necessary. Exactly how far you travel before taking another observation of a the same species is up for debate. Making an observation of every individual seems against the spirit of the competition and reduces the conservation/research value of each record.

Minimising Travel
Every minute of daylight travelling between locations is a minute not making observations. So to maximise your observations you'll want to minimise the number of locations travelled to each day. Ideally only one location each day, large enough for collecting observations for a full day. If you have the option, travelling to the location before sunrise and leaving at sunset can reduce the lost observing time to zero.

After Sunset
There are also possibilities for making additional observations after sunset (if you have the energy left after a full day of observing):

• Invertebrates can be attracted to outdoor lighting (or black lights or mercury vapour lights if you have the equipment).
• A hike around a familiar area with a headlamp and spotlight can reveal a wealth of nocturnal creatures.
• Insect traps can be set with the collection reviewed at the end of each day.
• Water samples from local waterways containing various water bugs can be collected during the day and reviewed during the evening.
• Frog calls can be recorded and uploaded.

Equipment
The equipment needed to maximise your observations is nothing more than a phone with a camera. As most observations will be of Plants, which don't flee when you get close, this will be sufficient. A compact camera or high-zoom bridge camera would also be suitable, however these cameras usually require the photos to be manually transferred to a computer at the end of the day, which adds a step to the workflow. A DSLR is perhaps less suitable due to its weight. Although if you have the equipment, using several cameras can be of value.

Diagnostic Features
Each observation should take a minimum of time, so taking multiple photos of an organism will obviously eat up time. Ideally, a single photo of each organism, showing the necessary diagnostic features is sufficient. The hard part is knowing exactly what those diagnostic features are for each Plant. This becomes far more difficult with Animal species, particularly Invertebrates. So if you really want to maximise your observations, skip the Insect/Arachnid you spot on the Plant that requires four photos to get an ID and instead just record the Plant.

Identification
Identification of what you've observed can wait until April 28th when the observation period is over. When uploading observations, aim to get them uploaded as soon as possible to give others maximal time to assist with the IDs. Simply uploading any observation you are not certain of the species as Plant/Animal/Fungi/Chromista is sufficient. Refining of the IDs can be done later.

Following the above will help to maximise the number of observations you take during the challenge, but unless you are 'in it to win it', this extreme approach may not be a particularly enjoyable way to spend four days.

Maximising Your Species

Locations
Maximising your species count will involve many of the tactics above. You'll still want to maximise your efforts during daylight hours and keep each observation time to a minimum. However visiting one location each day is likely to result in recording species from only a few different environments. To maximise your species count you'll want to visit as many different vegetation communities as possible. Each will have its own array of Plant, Animal and Fungi species.

Necessary Travel
Travel time between destinations is still considered lost time as no observations are being made. However the potential for locating new species is worth the loss. Each new vegetation community will have an array of easy to locate dominant and under-story species that differs from the community at the previous destination. The goal will be to maximise the number of vegetation communities visited while minimising the travel time between them.

Although various vegetation communities will boost the species count, Plants alone will be insufficient. You'll also want to record Animal species encountered along the way. Careful inspection of the Plants will likely result in an equal number of invertebrates being found. In most instances to get a species level ID, if at all possible from photos, multiple photos will be required.

Recording Birds
Recording Birds can also add quite a few species to the list. Consider visiting vegetation communities near waterways such as wetlands, estuaries and marine environments.

Coastal and Marine Species
Including coastal and marine environments will add many additional species. Diving might eat up a lot of time in preparation, but can contribute a large number of species. These would be a particularly beneficial contribution to the City Nature Challenge results. Alternatively a snorkel or beach/reef walk would also net a large number of species. Low tide occurs around midday on each of the challenge days so should provide a good opportunity to find intertidal species.

Suburban Weeds
A great way to boost your species count is to record species in suburban parks and waterways. These often include numerous 'garden escapee' species that are not found in such abundance in protected parks. (Although protected parks do have quite an array of introduced species throughout them). Also consider ForestrySA Pine plantations. While the Pines themselves would be a Casual observation, there are numerous weed species throughout the plantations worth recording. Roadsides too can be of value often containing some unusual weed species worth recording.

Tiny Taxa
Small invertebrate species are incredibly numerous, and if you have a camera suitable for capturing images of them they are certainly worth recording to boost your species numbers. Most Plants will have at least a few species on them, although finding them can be challenging. A single outdoor nightlight can attract dozens of species (if the weather is suitable). Recording these is a must if you wish to maximise your species count, so consider recording them during the City Nature Challenge Australia Moth Night on April 26th.

Difficult to Find Taxa
Other groups such as Mammals, Reptiles and Amphibians are going to be harder to intentionally locate and trying to add these to your species list may eat up a lot of time. However many should be encountered by chance while collecting other observations. Also if you know of a resident population that can be quickly located, they are well worth adding to your species list. Hopefully we can record at least one sighting of the locally rare Cunningham's Skink (Egernia cunninghami)

Often Overlooked Taxa
Don't forget to include some of the more overlooked groups of organisms:

• Fungi - Although early in the season, some species will be fruiting. Lichen are always present. Hard to ID to species from photos, but still worth recording
• Bryophytes - Mosses, Liverworts & Hornworts are often overlooked due to their size. Get the camera close and the species can often be determined
• Red, Green & Brown Algae - Numerous species of 'seaweed' litter many beaches, but are often overlooked while searching for more appealing species.
• Introduced Weeds - So common in parks that they are easy to ignore, but they are still wild species worth recording

After Sunset
Recording species after sunset will be necessary to maximise your species count. See the list of options for recording nocturnal species in the maximising observations section above.

Known Uncommon Species
If you know of the location of any uncommon species, try to incorporate stops at these locations to pick up those species. For some species there may be one or a few locations in the Greater Adelaide region that they exist. (As always, take appropriate care not to damage the organism or its local environment).

Equipment
To record all species from distant Birds to tiny invertebrates (in enough detail for a species ID), you'll need a few pieces of equipment. Your phone with camera or a compact camera will work well for most Plants and larger Animals. For Birds and some invertebrates a high-zoom bridge camera is a good option. It can reach most birds and capture reasonably small invertebrates. It is also lightweight (compared to a traditional DSLR) and there is no need to lose time changing lenses. A DSLR with telephoto lens can capture the distant wading Birds and wary Mammals & Reptiles. Switch to a macro lens to capture those skittish flying Insects. A compact camera with a macro setting or a phone with macro lens attachment can come in handy if you can get close enough to invertebrates without scaring them off, especially for those 5mm or smaller.

Diagnostic Features
To maximise your species count you'll want to ensure each observation can be identified to species level, or at least as close as possible. Depending on the taxa this may be easy with one photo, or impossible even with five photos. Knowing your target will help, but in general Plants will need a photo or two showing leaves, flowers, fruit. Invertebrates need close up photos from several angles at a minimum.

A Balanced Approach

Aiming to maximise either your observations or species count is potentially going to be more like work than fun, so a more balanced approach might be the way to go. Decide on a route to travel with several destinations covering various environments and see what you can find. Pick a forest, a wetland, an estuary, a reef. Mix it up to keep it interesting and to find many species you may have not otherwise encountered.

General Considerations

Depending on the destination you may need only a bottle of water, or a full backpack of gear. Take necessary gear appropriate to the situation, first aid kit, food/water, etc. Don't forget your batteries and SD cards. Don't lean over the cliff to photograph that rare Plant, inch too close to that resting Snake, or chase that Butterfly onto the main road. It may get you one more species on your list, but it isn't worth the risk.

Any questions before the challenge, ask in comments section below.

Publicado el marzo 16, 2020 07:51 MAÑANA por cobaltducks