The Second Survey
With the exception of the Eastern Red-spotted Newt, it is unlikely that you will capture any adult salamanders during the second and third surveys. However, these surveys are extremely important for capturing the larvae inhabiting the pond. The second survey should be carried out from mid-May to early-June depending on your geographical location. Sites in the extreme south of Ohio should be sampled during the second week of May, while those in the extreme north should be sampled during the first week of June.
The methods for the second survey are the nearly the same as the first survey. Walk around the site, placing the ten traps out at the same locations you previously marked with flags or survey tape. As water temperatures warm and oxygen levels in the pond decrease, it becomes very important that a small section of the funnel trap penetrates the water surface to allow any terrestrial animals captured access to air. On your data sheet, record the date and time of the trap placement, the air and water temperature, and the names of all people involved in placing the traps. Check the traps the following day, no more than 24 hours after they are placed at the site.
With each trap, move all salamander larvae captured into the plastic bag corresponding to the number of the trap they were captured in. When you have finished checking all of the traps, compare all of the larvae captured to determine how many morpho-species you have collected. Then, assign a generic identification to each morpho-species (“A,” “B,” etc.), preserve one representative of each morpho-species in the appropriate vial, and record the number caught in each trap. Write the date, including the year, on the top of each vial containing a specimen. Refer to the morpho-species concept for more help in identifying morpho-species. On your data sheet, record the date and time of the trap retrieval, the air and water temperature, and the names of all people involved in retrieving the traps and collecting the data. If any fish are captured or observed, note this in the appropriate box on the data sheet, and the species, if known.
In addition to the funnel-traps, it will be necessary to do some additional sampling using a dip-net after you have retrieved the traps for the second and third survey. Dip-net samples are used to capture any additional salamander larvae that may not have been captured in the funnel traps. Larvae of the Four-toed Salamander do not appear to be captured in funnel traps, so the use of a dip-net is very important when surveying for this species.
The type of dip-net used is not critical, so long as the mesh is small enough to capture any salamander larvae and sturdy enough to withstand the vegetation and debris of the site. You will probably want to wear hip boots or waders when dip-netting the site, to allow you to go into the water. Sweep the net through the water in all of the different habitats available at the site. You will need to sweep into the muck of the bottom of the pond, as many salamander larvae hide here. With each sweep, move any captured salamander larvae into a sorting tray or bucket containing water. Continue dip-netting for approximately 30 minutes, being sure to sample all of the available habitat types at the site.
When you have finished dip-netting, examine the larvae you have captured. Again, it is not important for you to identify the species that you have captured, only to recognize any larvae that are different than the species captured in the traps. Four-toed Salamander larvae are readily distinguishable by the dorsal (top) fin that extends well forward onto the body, and the presence of four toes on the hind feet. For each new species encountered when dip-netting, assign a new morpho-species identification (“A,” “B,” etc.), preserve one representative of each morpho-species in the appropriately marked vial, and record the number of each captured. Record this information in the row marked “Dip-net” on your data sheet. Species captured while dip-netting that were also present in the traps do not need to be recorded.
The Third Survey
The third and final survey of your site should occur between the end of June (southern Ohio) and the first of July (northern Ohio). You are to follow the same procedures as for the second survey, using the funnel traps and dip-netting for additional species. Water temperatures will be at their highest at this time of year, resulting in very low oxygen levels in the water. Be sure that all of the traps penetrate the water surface, allowing an air pocket for captured organisms.