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Nest Vegetation MeasurementsSaltmarsh Habitat & Avian Research ProgramStandard Operating ProcedureLast updated 21 May 2019

Survey Goal:To characterize the nesting habitat of tidal marsh birds (5 focal species - Saltmarsh Sparrows, Nelson’s Sparrows, Seaside Sparrows, Clapper Rails, Willets, and Black Ducks) in marshes across the breeding range of the saltmarsh sparrow.

General Approach:Vegetation structure and composition measurements are observed in 1 m2 quadrats at nest and randomly-selected, non-nest points at SHARP demographics sites to characterize nesting habitat in the context of available nesting habitat.

SHARP SOP 21 May 2019

Version historyDate Revised Summary of Changes Reason for Change Author Notes

May 13, 2014 NOT REC NOT REC NOT REC

May 31, 2016 New nest structure measurements added with accompanying photos

A. Kocek launched a new project requiring more detailed nest structure data

Alison Kocek

May 21, 2019 Various. The largest changes include:1. Implementing different disks for

different focal species.2. Specification and clarification

of methods (e.g., live and dead veg considered for tallest veg, definition of average height, generation of randomly-selected points with 6 m buffer, added figures)

3. Elimination of nest orientation measurement

4. Approval of additional nest structure measurements introduced by A. Kocek in 2016-2017 (e.g., vertical structure)

5. Create “unvegetated” category for percent cover which includes bare ground, standing and open water

6. Formatting, including adding version history

Great SOP clean up of 2019 Contributions made by PI’s and graduate students on SHARP call. Final edits completed by Kate Ruskin, Emily Patterson, and Brian Olsen.

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GENERAL INSTRUCTIONS Nest vegetation datasheets are included on the back of the nest card so that all the information associated with a particular nest is kept together, whereas non-nest points should be printed on separate datasheets.

The nest measurements occur in two time-frames: 1. Initial Veg Survey: Nest Structure Measurements: Structural measurements of the nest2. Second Veg Survey: Surrounding Veg: Vegetation measurements of the nest site (1 m2

surrounding nest) and optionally, at a paired, random location within the plot (if interested in characterizing nest site selection).

Part 1 should occur on the day of finding a nest with at least one egg or as soon as possible afterwards to accurately measure the nest before its structure or cover is changed by disturbances (nest checks, nest predation/flooding) or the normal processes associated with nestling development (some nests become more exposed or droop as chicks grow). Note: Do NOT take measurements on a nest that is under-construction.

Part 2 should be completed within one week of observing that the nest is no longer active. To minimize disturbance to the nest site, these measurements should NOT be taken while the nest is active. Ideally, complete these measurements on the first day the nest is no longer active and definitely within 1 week of becoming inactive. If also measuring vegetation at paired random locations, complete one paired random point within one week of measuring the nest site – ideally on the same day as part 2 of the nest measurements.

REQUIRED EQUIPMENT

● Part 1: GPS unit, wooden/plastic ruler, nest canopy disks (all species)

● Part 2: GPS unit, 1 m2 quadrat (e.g., four 1 m long pvc pipes placed in a square on the ground), meter stick, list of randomly-selected points for the site.

PART 1: NEST STRUCTURAL MEASUREMENTS On the day of finding an active nest with at least one egg, gather the following measures, taking care not to alter the nest canopy or the surrounding vegetation:

a. Basic information: nest veg survey date, observer, site, SHARPNestID, Photos Taken? Y/N

b. Nest Height

● Distance from cup lip to ground (A)

● Distance from cup bottom to ground (B)

● Distance from cup center to lip (C) – This measurement is no longer collected. This measurement spans from the lip of the nest bowl to the bottom of the bowl, INSIDE the bowl. In other words, it is not simple A minus B because it does not include the thickness of the bowl bottom. Eggs should be carefully removed from the nest in order to perform this measurement and should be performed in conjunction with iButton placement (if occurring) to reduce handling time for eggs.

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c. % of Canopy Disk Visible from Above: Print the dotted ‘Nest Canopy Disks’ for all species on durable paper (e.g., cardstock, or computer paper ‘laminated’ with packing tape). Delicately place the canopy disk for the appropriate species into the nest cup (lay atop the eggs as eggs do not need to be removed) without disturbing the woven canopy or live/thatch covering of the nest. Visually estimate from above what % of the disk is visible from above (i.e., If only 20% of the disk is visible, then 20% is your answer). Note: Prior to 2019, different sized nest disk for different species had not been introduced across all SHARP demographic sites (sites were previously using the one sparrow-sized disk for all species, though CT in 2017-2018 has a separate database with species-specific disk data for WILL and CLRA).

d. Nest Entrance Orientation (°): This measurement is no longer collected. Viewing the center of the nest as the center of a compass, what is the bearing of the nest’s entrance (if there is a clear entrance) in degrees? The compass should be placed pointing out from the nest in the direction of the entrance. Please note that some nests have an entrance and an exit, and some have entrances from above. If there is both an entrance and an exit, choose the one that appears to be used as an entrance or used more often, and record the bearing for that opening, recording the bearing for the other entrance/exit in Notes, along with an explanation that there were two openings. If the entrance is from above, choose “NOT REC” for bearing and make a note that the entrance was from above.

e. Nest Location: Measurements for this section will be used to better understand how and where individuals build their nest within a marsh. We seek to characterize the woven canopy some birds build over the nest, the vegetation the nest was built under but not incorporated into the nest structure, and the vegetation species the nest is attached to in order to give it stability. Not all items will apply to every species or nest.

● Nest is Under (circle one): Was the nest built under vegetation that was not woven into a canopy?

i. Exposed: The nest is not under any vegetation (alive or dead) that is not part of the woven canopy of the nest (see below for definition of woven canopy). A nest would be considered exposed even if it has a fully woven canopy if no additional vegetation directly covers it.

ii. Under Thatch: The nest was intentionally built under a layer of dead thatch.iii. Under Live: The nest was built under a layer of live vegetation.iv. Under Both: The nest was built under both dead thatch and live vegetation.

● Woven Nest Canopy (circle one): A woven canopy is vegetation pulled over the nest cup and secured by the bird. The distinguishing feature here is that the vegetation was manipulated in some way by the attending birds; it is not simply vegetation that overhangs the nest. Woven coverings can be created with overhanging vegetation above them.

i. None: There is no intentionally woven canopy covering the nest. ii. Partial: A partial canopy is a woven canopy that covers <50% of the nest

cup. This is a visual estimate and you will have to use your best estimate of coverage without causing harm to the nest structure. A partial canopy is often obvious and occurs when a tightly woven canopy that was built over only half of the nest cup or because it is very loosely woven and the small number of strands it consists of covers less than 50% of the nest cup. Partial should only be used when it is obvious that the woven canopy clearly does not provide coverage to a large portion of the nest.

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iii. Complete: A complete canopy covers >50% of the nest cup. This often occurs when a cover is more tightly woven and covers the majority of the nest cup. This is a visual estimate, so use your best judgement when determining if a canopy is partial or complete.

● Woven Nest Canopy Live/Dead (circle one): If there is a woven nest canopy, is it woven out of live vegetation, dead thatch, both, or NA (there is no woven nest canopy)?

● Woven Nest Canopy Veg Species (list all): If there is a woven canopy, what type(s) of vegetation is the woven canopy made up of? (i.e. Spartina patens, Spartina alterniflora, etc.) Please list all species, and note that “thatch” is not an option because whether the veg is dead is covered by the previous field (e.g. a nest with a canopy woven of S. patens thatch will be listed as: woven nest canopy- dead, woven nest canopy veg species- S. patens).

● Vertical structure (nest is attached to) - Live/Dead (circle one): The nest cup is generally attached to a stem or multiple stems of vegetation that keeps the nest cup up off the ground and from floating away in a flood. Are the stem(s) the nest is attached to live vegetation, dead thatch, both, or nothing (NA)? The best way to determine this is to look at the back (away from the entrance) or bottom of the nest to see what the nest cup is woven onto. This should not require any great disturbance to a nest.

● Vertical Structure Veg Types (pick multiple or single and list all): i. Multiple Stems: If the nest cup is attached to by multiple stems, identify all

species of vegetation among those stems. Record NA if the nest is attached to 0-1 stems. This usually includes: Spartina patens, Distichlis spicata, Juncus gerardii, and possibly Spartina alterniflora.

ii. Single Stem: If the nest cup is attached by a single stem, identify the species of vegetation for that stem. Record NA if the nest is attached to 0 or >1 stems. This usually occurs with: Iva frutescens and sometimes Spartina alterniflora.

Photo examples of nest location and woven nest canopy classifications.

Nest Location: Exposed Nest Location: Under Thatch

Nest Location: Under Both (Live & Thatch)

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Woven Nest Canopy: None

(No natural or intentionally woven vegetation covers the nest.)


(Natural dead vegetation cover but the bird did not shape it in any way to make a woven canopy.)


(The nest was built directly under a bunch of live and dead S. alterniflora and no vegetation was woven into a canopy.)

Nest Location: Under Live

Woven Nest Canopy: Partial

(Woven canopy covers <50% of nest cup even though live natural/unwoven vegetation

may completely cover the nest cup)

Nest Location: Under Live

Woven Nest Canopy: Complete

(Woven canopy covers >50% of nest cup and live

natural/unwoven vegetation also covers the nest cup)

Nest Location: Exposed

Woven Nest Canopy: Complete

(Woven canopy covers >50% of nest cup and the nest was

built such that thatch natural/unwoven vegetation

does not intentionally cover the nest cup).

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PART 2: NEST SITE AND RANDOM POINT CHARACTERISTICS Within one week of observing that a nest is no longer active, gather the following measures at the nest site and, optionally, at a paired point chosen randomly within the same plot. Before the start of the field season, generate 100 randomly-selected vegetation survey points using the Random Points tool in ArcGIS, working from a polygon of the demographic study site. From 2019, we will apply a 6 m buffer in this tool based on the typical accuracy of handheld GPS units. Prior to 2019, demographic crews employed different methods of buffering during random point selection (Maine used no buffer, NY used 6 m buffers, UNH used 10 m buffers). If a random point falls on a mudflat or in open water, cross out that random point and move to the next on the list. A random point that falls within 100% wrack should still be surveyed. Each measurement below should be gathered within 1-m2 square centered over the nest or random point. Collection of these measurements should be avoided during high tides when shorter vegetation types and thatch depth may be difficult to measure.

a. Percent Cover of Vegetation: Visually estimate the percent cover of each vegetation cover type (list below). Rare cover types that are not listed in the database should be included in the ‘Other’ field. When you record a nonzero value in the ‘Other’ field, please decompose the percentages and species in the ‘Notes’ field. Note: we are counting BOTH live and dead vegetation together (e.g., if your quadrat contains 40% dead Spartina patens and 20% live S. patens, the total for that species would be 60%). Be sure your total cover adds up to 100% before leaving the nest/random point.

Possible vegetation cover types: 1. Wrack (dead vegetation washed onto the marsh by the tide, differs from

thatch in that it is unattached to the ground) 2. Unvegetated1 (includes bare ground2 , standing water, open water3)3. Spartina patens 4. Spartina alterniflora 5. Distichlis spicata 6. Juncus sp. 7. Iva / Baccharis sp.8. Phragmites australis9. Salicornia sp.10. Other (any cover type(s) not listed above or rare for your site)

b. Average Height of Vegetation Crown (midpoint of each side of the quadrat and plot center - 5 points): Visually estimate the average height of the crown of vegetation in an area around the measurement point that is approximately the size of a sparrow nest (Figure 2). The “crown” is the highest relatively continuous layer of vegetation (live or dead). A useful rule of thumb is to ask how high would you hold your hand to show “how tall is the vegetation out there?” Don’t overthink it and do your best. It’s important to note that if the vegetation crown is thatch, then this measurement will equal the thatch measurement.

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Figure 2. Configuration of nest measurements for random points (left) and measurements at midpoints of quadrats (both nest and random points),plot center for random points only (right).

c. Height AND Species of the Tallest Vegetation (midpoint of each side of the quadrat and plot center - 5 points) This should be a piece of vegetation that is within an area the size of a sparrow nest around the measurement point. The vegetation should NOT be pulled up from the ground but measured at its highest natural height within the measurement window (even if taller parts of the plant exist outside of the window) (figures 2, 3). With the species, record whether the vegetation is live or dead (e.g., ‘live S. alterniflora’, ‘dead S. patens’). Note: prior to 2019, NY considered only live vegetation for tallest, and other sites may have inconsistently included dead vegetation in this measurement though it was likely a rare occurrence.

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Figure 3. Configuration of nest measurements for nest points (left) and plot center for nest quadrats only (right).

d. Thatch Depth: (midpoint of each side of the quadrat and plot center - 5 points). Measure the height of the top of thatch. For our purposes, thatch is defined as the (mostly) horizontal layer of dead (last year’s) vegetation on the marsh surface (think “attached and relaxed”, not upright sprigs of dead veg; figures 2, 3). It is generally present in high marsh (Spartina patens) and is rarely present in low marsh (Spartina alterniflora).Note: For nest quadrats, for the center point, consider the area of the nest (figure 3), but not the nest bowl itself or vegetation maneuvered by the female (e.g., measure thatch or tallest vegetation at the highest naturally laying point, not the lip of the nest bowl or a completely woven canopy).

1 Category instituted in 20192 Areas that are generally bare ground except during the highest tides should be considered bare ground.3 Open water should only be used in areas that contain water a vast majority of the time (e.g., pannes, pools, and creeks), as opposed to 1-3 cms of standing water in a quadrat that is vegetated. Note that this may have been inconsistently applied prior to 2019, with both water bodies and standing water in an otherwise vegetated plot counted toward the ‘open water’ total.

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