Daniel K. Inouye Solar Telescope Hawaiian Petrel Monitoring Project on Haleakalā
H. Chen, C. Ganter, R. Geelhood, & J. Panglao
The Daniel K. Inouye Solar Telescope (DKIST) Resource Management Team, in accordance with the DKIST Habitat Conservation Plan (HCP) and the Final Biological Opinion (BO) of the U.S. Fish and Wildlife Service (USFWS, 1-2-2011-F-0085) began monitoring Hawaiian Petrel burrows on Haleakalā since 2011, nearly 2 years prior to actual construction start date in December 2012.
- The implementation of the mitigation measures prescribed in the HCP and BO has benefited the Hawaiian Petrel population in DKIST’s Conservation Area, both in terms of increased productivity and reduced predation rates.
- In addition, the fencing and outplanting of Haleakalā Silversword seedlings has facilitated the Haleakalā Silversword recovery process.
Introduction
The Daniel K. Inouye Solar Telescope (DKIST) Resource Management Team, in accordance with the DKIST Habitat Conservation Plan (HCP) and the Final Biological Opinion (BO) of the U.S. Fish and Wildlife Service (USFWS, 1-2-2011-F-0085) began monitoring Hawaiian Petrel burrows on Haleakalā since 2011, nearly 2 years prior to actual construction start date in December 2012.
- The implementation of the mitigation measures prescribed in the HCP and BO has benefited the Hawaiian Petrel population in DKIST’s Conservation Area, both in terms of increased productivity and reduced predation rates.
- In addition, the fencing and outplanting of Haleakalā Silversword seedlings has facilitated the Haleakalā Silversword recovery process.
Rodent Bait Boxes around HO:
- 47 Protecta ™ tamper resistant rat bait boxes were placed every 30 ft. along the perimeter of all permanent structures and trailers within Haleakalā Observatory (HO)
Long-term Rodent Grid
- A long-term rodent grid consisting of 35 Good Nature A-24 rodent killing traps located 75 meters apart (50 year commitment)
|
Table 1. Effectiveness of DKIST Long-Term Rodent Control Grid Between 2013 and 2017 at the Summit of Haleakala, Maui – Rodents Removed |
||||
|
Grid Stage |
One1 |
Two2 |
Three3 |
Total |
|
Time Period |
04/02-05/28/2013 |
05/29/2013-04/20/2015 |
05/07/2015 – 12/31/2017 |
|
|
Rodent Captured |
|
|
|
|
|
Field Mice |
n/a |
42 |
105 |
52 |
|
Roof Rats |
n/a |
16 |
4 |
20 |
|
Norwegian Rats |
n/a |
9 |
0 |
9 |
|
Unidentifiable Rats |
n/a |
21 |
125 |
33 |
|
Subtotal |
n/a |
88 |
24 |
114 |
|
A-24 Trap Hits4 |
n/a |
n/a |
59 |
59 |
|
Total Rodents Removed by Different Trap Types |
173 |
|||
|
1: 48-meter bait box grid of 51 stations- eight 1-oz Ramik™ diphacinone blocks per- Protecta ™ tamper-resistant rat bait box. 2: 48-meter bait box grid of 51 stations- T-Rex rat and mouse snap traps baited with peanut butter in each Protecta ™ tamper-resistant rat bait box and mouse bait box. 3: 47 Protecta ™ tamper-resistant rat bait boxes baited with six 1-oz Ramik™ diphacinone blocks every 30 ft. along the perimeter of all permanent structures and trailers within Haleakalā Observatory (HO) plus 35 A-24 traps with peanut butter bait in 75 meter grid outside of HO. 4: A-24 estimate based on trap counter registered trap triggered without carcasses being found. 5. One Field Mouse and an unidentifiable Rat killed by predator control grid A-24 trap. |
||||
- The traps in DKIST’s long-term rodent control grid have removed a total of 114 rodents between all trap types.
-
- In addition, it can be estimated that the A-24 traps may have also removed as many as 59 unidentifiable rodents for which the carcasses were not located.
- An estimated total of 162 roof rats were killed by rodenticide, giving an estimated total of 335 rodents which have been removed by long-term rodent control grid traps and rodenticide (Table 1).
Rodent Population Monitoring: (*Not required by the HCP or BO) Used to evaluate the impacts of the long-term rodent control grid relative to the local rodent population.
-
- 20 bait box stations (10 at each site) each equipped with a T-Rex rat and a T-Rex mouse trap housed in Protecta ™ tamper resistant bait boxes 48 meters apart.
- Pre-baited with Peanut Butter one week before traps were set
- Each monitoring period consisted of 2 trap nights
- Rodent population monitored seasonally in March, June, September, and December of each year.
- The DKIST HCP requires the establishment of a Conservation Area to mitigate the potential negative effects related to construction of the DKIST facility. In addition, the HCP also specifies the need to establish a Control Site to compare and evaluate the DKIST Resource Management Team’s conservation efforts within the HCP Conservation Area. Both of these areas have been established and maintained since 2011.
-
- The Conservation Area is located between approximately 8,800 and 10,000 ft. (2,686 to 3,048 m) in elevation, and was estimated to be 328 acres (133 ha). The topography within the Conservation Area is rugged and barren, and the elevation drops with an average slope greater than 30 percent (DKIST 2010).
- The Control Site encompasses 80 acres and is one kilometer west of the west boundary of the Conservation Area, just north of the Skyline Trail, at an elevation of 8,700 to 9,300 ft. (2652 to 2835 m). The topography within the Control Site is similar to that of the Conservation Area.
Site Description
- The DKIST HCP requires the establishment of a Conservation Area to mitigate the potential negative effects related to construction of the DKIST facility. In addition, the HCP also specifies the need to establish a Control Site to compare and evaluate the DKIST Resource Management Team’s conservation efforts within the HCP Conservation Area. Both of these areas have been established and maintained since 2011.
-
- The Conservation Area is located between approximately 8,800 and 10,000 ft. (2,686 to 3,048 m) in elevation, and was estimated to be 328 acres (133 ha). The topography within the Conservation Area is rugged and barren, and the elevation drops with an average slope greater than 30 percent (DKIST 2010).
- The Control Site encompasses 80 acres and is one kilometer west of the west boundary of the Conservation Area, just north of the Skyline Trail, at an elevation of 8,700 to 9,300 ft. (2652 to 2835 m). The topography within the Control Site is similar to that of the Conservation Area.
- The Hawaiian Petrel or ‘Ua’u (Pterodroma sandwichensis) was listed as endangered on March 11, 1967
- Medium-sized seabird in the same family as other petrels, shearwaters, and fulmars
- Hawaiian Petrels once were abundant and widely distributed throughout the Hawaiian Islands
- Highly synchronous in breeding with clear evidence indicating intra-island variation in breeding phrenology in Hawaii with the Haleakalā colonies breeding approximately one month earlier than Kaua’i, Lana’i, and Hawai’i Island.
- Hawaiian Petrels nest in high elevation burrows located beneath rock outcrops, along slopes, an edges of lava flows where there is suitable soil that allows for excavation.
- Burrows are excavated to a depth of one to two meters, but can sometimes reach a length of up to five meters or more.
- Pairs are site tenacious, returning to the same burrow year after year.
Hawaiian Petrel/'Ua'u
- The Hawaiian Petrel or ‘Ua’u (Pterodroma sandwichensis) was listed as endangered on March 11, 1967
- Medium-sized seabird in the same family as other petrels, shearwaters, and fulmars
- Hawaiian Petrels once were abundant and widely distributed throughout the Hawaiian Islands
- Highly synchronous in breeding with clear evidence indicating intra-island variation in breeding phrenology in Hawaii with the Haleakalā colonies breeding approximately one month earlier than Kaua’i, Lana’i, and Hawai’i Island.
- Hawaiian Petrels nest in high elevation burrows located beneath rock outcrops, along slopes, an edges of lava flows where there is suitable soil that allows for excavation.
- Burrows are excavated to a depth of one to two meters, but can sometimes reach a length of up to five meters or more.
- Pairs are site tenacious, returning to the same burrow year after year.
Hawaiian Petrel burrow monitoring began in 2011
- The DKIST Resource Management Team begins annual burrow monitoring in February-March by visiting all previously recorded burrows.
- Newly identified burrows are documented as they are discovered and a systematic search of the DKIST Conservation Area and Control Site in conducted.
- Signs of petrel activity (droppings, footprints, feathers, egg shells, smell, and other body parts) are used to determine activity around burrows.
- Toothpicks are placed vertically along the entrance of each burrow to monitor petrel movement in and out of the burrows.
-
- Fallen or height-altered toothpicks suggest recent activity, while undisturbed toothpicks indicate no activity.
- Burrows that were classified as “Active” were then re-checked twice a month until September. Bushnell HD camera traps were then installed at burrows still displaying signs of activity. Camera traps remain in operation until November when all the remaining chicks have fledged.
-
- A burrow was defined to be “Successful” by the presence of petrel chick down feathers at the burrow entrance, and disturbed toothpicks after mid-September, and/or evidence provided by video monitoring and data collected from the camera traps.
- Burrows classified as “Failed” showed signs of activity during initial search, but no further signs were observed while conducting the subsequent rechecks
-
- “Failed” burrows were either occupied by non-breeders, the nest was abandoned, or the chick did not reach fledgling age.
-
Silversword Outplanting:
800 seeds from four flowering flowering Haleakalā Silversword, 'Ahinahina (Argyroxiphium sandwicense subsp. macrocephalum) plants within the DKIST Conservation Area were collected on November 18, 2014 by the subcontractor Starr Environmental, under DLNR permit.
The seeds were turned over to Haleakalā National Park (HNP) for propagation.
DKIST Resource Management team carefully checked the source area during its June 2015 monitoring for natural regeneration from the Silversword seed bank in the area from which the seeds were collected.
Burrow Monitoring and Silversword Outplanting
Hawaiian Petrel burrow monitoring began in 2011
- The DKIST Resource Management Team begins annual burrow monitoring in February-March by visiting all previously recorded burrows.
- Newly identified burrows are documented as they are discovered and a systematic search of the DKIST Conservation Area and Control Site in conducted.
- Signs of petrel activity (droppings, footprints, feathers, egg shells, smell, and other body parts) are used to determine activity around burrows.
- Toothpicks are placed vertically along the entrance of each burrow to monitor petrel movement in and out of the burrows.
-
- Fallen or height-altered toothpicks suggest recent activity, while undisturbed toothpicks indicate no activity.
- Burrows that were classified as “Active” were then re-checked twice a month until September. Bushnell HD camera traps were then installed at burrows still displaying signs of activity. Camera traps remain in operation until November when all the remaining chicks have fledged.
-
- A burrow was defined to be “Successful” by the presence of petrel chick down feathers at the burrow entrance, and disturbed toothpicks after mid-September, and/or evidence provided by video monitoring and data collected from the camera traps.
- Burrows classified as “Failed” showed signs of activity during initial search, but no further signs were observed while conducting the subsequent rechecks
-
- “Failed” burrows were either occupied by non-breeders, the nest was abandoned, or the chick did not reach fledgling age.
-
Silversword Outplanting:
800 seeds from four flowering flowering Haleakalā Silversword, 'Ahinahina (Argyroxiphium sandwicense subsp. macrocephalum) plants within the DKIST Conservation Area were collected on November 18, 2014 by the subcontractor Starr Environmental, under DLNR permit.
The seeds were turned over to Haleakalā National Park (HNP) for propagation.
DKIST Resource Management team carefully checked the source area during its June 2015 monitoring for natural regeneration from the Silversword seed bank in the area from which the seeds were collected.
- A Conservation fence consisting of three strands of steel wire-enforced Poly-tape installed horizontally along the entire fence length in compliance with the HCP and BO was completed in November 2013.
-
- 4.23 km (2.63 mi) of fence enclosing 126.53 ha (312.66 acres) of the Conservation Area.
Predator Trap Grid:
- 130 meter grid alternating Havahart cat traps and Good Nature A-24 mongoose traps (40 cat traps and 42 mongose traps)
-
- Each Havahart cat trap was equipped with a Telonics TBT-600NH or 503-1 trapsite transmitter to allow the traps to be monitored at least every other day to avoid petrel by-catch and to ensure the welfare of the trapped animals.
- Initially peanut butter was used in the A-24 traps, and 3 roof rats were killed.
- The bait was changed to predator-specific bait in order to better lure mongoose. These baits were rotated monthly.
-
- salmon oil, synthetic cat nip oil, "Violator 7", and "Feline fix"
- After switching bait from the peanut butter to the predator-specific bait, no additional predators were captured.
In 2012, camera footage revealed that a feral cat had visited five different burrows and entered at least one. A Havahart trap was set near burrow SC37 on September 13, 2012 just below the MEES Observatory. Friskies brand cat food was used at bait. The cat was captured and removed from the site. There has only been one additional cat sighting (in 2015) in the Conservation Area since the sighting and capture in 2012.
In 2014, the Havahart traps caught 2 roof rats and not cats.
1 field mouse was captured and killed in the A-24 traps in the beginning of 2017.
Predator Population Monitoring: (Not required by the HCP or BO) Provides visual evidence and confirmation of presence or absence of predators within the Conservation Area and Control Site, and help to achieve a Net Recovery Benefit through an adaptive management approach.
-
- Ungulate and predator population monitoring data was collected using 20 Bushnell Trophy Cam HD camera traps, 10 at each site (Conservation Area and Control Site), at randomly selected locations using ArcGIS 10.0.
Predator Control
- A Conservation fence consisting of three strands of steel wire-enforced Poly-tape installed horizontally along the entire fence length in compliance with the HCP and BO was completed in November 2013.
-
- 4.23 km (2.63 mi) of fence enclosing 126.53 ha (312.66 acres) of the Conservation Area.
Predator Trap Grid:
- 130 meter grid alternating Havahart cat traps and Good Nature A-24 mongoose traps (40 cat traps and 42 mongose traps)
-
- Each Havahart cat trap was equipped with a Telonics TBT-600NH or 503-1 trapsite transmitter to allow the traps to be monitored at least every other day to avoid petrel by-catch and to ensure the welfare of the trapped animals.
- Initially peanut butter was used in the A-24 traps, and 3 roof rats were killed.
- The bait was changed to predator-specific bait in order to better lure mongoose. These baits were rotated monthly.
-
- salmon oil, synthetic cat nip oil, "Violator 7", and "Feline fix"
- After switching bait from the peanut butter to the predator-specific bait, no additional predators were captured.
In 2012, camera footage revealed that a feral cat had visited five different burrows and entered at least one. A Havahart trap was set near burrow SC37 on September 13, 2012 just below the MEES Observatory. Friskies brand cat food was used at bait. The cat was captured and removed from the site. There has only been one additional cat sighting (in 2015) in the Conservation Area since the sighting and capture in 2012.
In 2014, the Havahart traps caught 2 roof rats and not cats.
1 field mouse was captured and killed in the A-24 traps in the beginning of 2017.
Predator Population Monitoring: (Not required by the HCP or BO) Provides visual evidence and confirmation of presence or absence of predators within the Conservation Area and Control Site, and help to achieve a Net Recovery Benefit through an adaptive management approach.
-
- Ungulate and predator population monitoring data was collected using 20 Bushnell Trophy Cam HD camera traps, 10 at each site (Conservation Area and Control Site), at randomly selected locations using ArcGIS 10.0.
Hawaiian Petrel Reproductive Success
- As new burrows were located each year, the number of burrows monitored increased from 272 in 2011 to 392 in 2017.
- 2017 was the first year that no new burrows were recorded in the Control Site
|
Table 1. Hawaiian Petrel Burrows and Reproductive Success in DKIST HCP Conservation Area and Control Site on Haleakalā, Maui, Hawaii (Cons. =Conservation Area, Cont. =Control Site). |
||||||||||||||||
|
|
Year |
2011 |
2012 |
2013 |
2014 |
2015 |
2016 |
2017 |
||||||||
|
Status |
Location |
Cons. |
Cont. |
Cons.1 |
Cont. |
Cons.2 |
Cont. |
Cons.3 |
Cont. |
Cons.4 |
Cont. |
Cons. |
Cont. |
Cons. |
Cont. |
|
|
Old Found in prior years) |
Active |
73 |
0 |
140 |
6 |
122 |
7 |
158 |
7 |
154 |
7 |
106 |
8 |
163 |
10 |
|
|
Successful |
24 |
0 |
16 |
0 |
26 |
0 |
42 |
1 |
29 |
2 |
48 |
0 |
50 |
0 |
||
|
Non productive |
49 |
0 |
124 |
6 |
96 |
7 |
116 |
6 |
125 |
5 |
58 |
8 |
1135 |
10 |
||
|
Not Active |
38 |
0 |
103 |
15 |
151 |
18 |
128 |
19 |
143 |
22 |
200 |
23 |
169 |
23 |
||
|
Not a Burrow |
10 |
0 |
15 |
0 |
8 |
0 |
2 |
0 |
0 |
0 |
5 |
0 |
0 |
0 |
||
|
New (found during year) |
Active |
86 |
14 |
13 |
3 |
3 |
1 |
7 |
3 |
14 |
2 |
13 |
2 |
26 |
0 |
|
|
Successful |
8 |
0 |
0 |
0 |
1 |
0 |
2 |
0 |
0 |
0 |
1 |
0 |
3 |
0 |
||
|
Non productive |
78 |
14 |
13 |
3 |
2 |
1 |
5 |
3 |
14 |
2 |
12 |
2 |
23 |
0 |
||
|
Not Active |
39 |
7 |
9 |
1 |
3 |
0 |
1 |
0 |
0 |
0 |
8 |
0 |
1 |
0 |
||
|
Not a Burrow |
5 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
|
Subtotal |
Old |
121 |
0 |
258 |
21 |
281 |
25 |
288 |
26 |
297 |
29 |
311 |
31 |
332 |
33 |
|
|
New |
130 |
21 |
22 |
4 |
6 |
1 |
8 |
3 |
14 |
2 |
21 |
2 |
27 |
0 |
||
|
Total |
251 |
21 |
280 |
25 |
287 |
26 |
296 |
29 |
311 |
31 |
332 |
33 |
359 |
33 |
||
|
Nesting Activity % |
67.37 |
66.67 |
57.74 |
36.00 |
44.80 |
30.77 |
56.12 |
34.48 |
54.02 |
29.03 |
35.84 |
30.30 |
52.65 |
30.30 |
||
|
Nesting Success % |
20.13 |
0.00 |
10.46 |
0.00 |
21.60 |
0.00 |
26.67 |
10.00 |
17.26 |
22.22 |
41.18 |
0.00 |
28.04 |
0.00 |
||
|
1. Seven of the old burrows recorded in 2012 were burrows that were marked prior to 2011, but were found in 2012. 2. One of the old burrows recorded in 2013 was marked prior to 2011, but was found in 2013. 3. Including one burrow separated from an old burrow in 2014. 4. Including one burrow separated from an old burrow in 2015. 5. Including two unknown outcomes due to camera failure. |
||||||||||||||||
- In the Conservation Area, the largest number of active burrows since 2011 was recorded in 2017.
-
- There were 189 active burrows in 2017, which is a 57% increase over 2016 (119).
- Nesting Activity % (52%) showed a significant increase compared to 36% in 2016 (χ2 =7.617, P<0.05, df=1, Figure 8)
- The successful burrow number increased 8% to 53 in 2017
- Nesting Success % (number of fledglings/number of active burrows) increased 77.5% after the conservation measures were implemented in the Conservation Area
- “Nesting Success %” was 28.0%, somewhat lower than it was in 2016 (41.2%, χ2 = 2.801, P>0.05, df=1) (Figure 10).
- The annual Hawaiian Petrel productivity (number of chicks produced) in the Conservation Area increased 82.3% after the HCP was fully implemented
Hawaiian Petrel Mortality
In order to better quantify the annual benefit to the population, we first determined the expected mortality rate for both chicks and adults, respectively.
The annual chick/adult benefit is the difference between the expected mortality and the actual number of mortalities recorded each year. Finally, these annual benefit values for years 2013-2017 were summed to determine the total Net Recovery Benefit.
As of the end of the 2017 season, it is estimated that the predation of 22 chicks and 12 adult Hawaiian Petrels has been prevented due to the predator control measures implemented by the DKIST Project. This net reduction in predation of 34 birds represents a significant Net Recovery Benefit to the species (Table 2).
|
Table 2. Hawaiian Petrel Predation Rates Before (2011-2012) And After (2013-2017) DKIST Mitigation Efforts in the DKIST Conservation Area at the Summit of Haleakala, Maui. |
||||||||
|
Year |
2011 |
2012 |
2013 |
2014 |
2015 |
2016 |
2017 |
Total |
|
Active Burrows |
159 |
153 |
125 |
165 |
168 |
119 |
189 |
|
|
Chicks Produced |
38 |
17 |
30 |
44 |
29 |
49 |
54 |
|
|
Chicks Fledged |
32 |
16 |
27 |
44 |
29 |
49 |
53 |
|
|
Chicks predated |
6 |
1 |
3 |
0 |
0 |
0 |
1 |
|
|
Expected Chick Predation at 12.7% |
|
|
3.82 |
5.60 |
3.69 |
6.24 |
6.87 |
|
|
Annual Chick Benefit |
|
|
0.82 |
5.60 |
3.69 |
6.24 |
5.87 |
22.22 |
|
Annual Chick Predation Rate |
0.16 |
0.06 |
0.10 |
0.00 |
0.00 |
0.00 |
0.02 |
|
|
Adults predated |
1 |
3 |
0 |
1 |
0. |
1 |
1 |
|
|
Expected Predation at 3.6% |
|
|
2.18 |
3.20 |
2.11 |
3.56 |
3.93 |
|
|
Annual Adult Benefit |
|
|
2.18 |
2.20 |
2.11 |
2.56 |
2.93 |
11.98 |
|
Annual Adult Predation Rate |
0.01 |
0.009 |
0.00 |
0.01 |
0.00 |
0.01 |
0.01 |
|
- In 2017, 6 of the 20 burrows being monitored by cameras were successful in fledging petrels. We also installed 84 camera traps at active burrow sites outside of the Mees Observatory area (including 7 in the Control Site). Among these camera traps, the exact fledging dates at 47 burrows were recorded. Based on 53 fledging date recordings, the fledging dates were between October 4 and November 4 (median date: October 21) (Figure 17).
- The recorded events of 2017 confirmed that Hawaiian Petrels begin fledging from their burrows during the latter part of September, as has been the case in previous breeding seasons. The 3rd and 4th weeks of October accounted for the largest number of fledged chicks. By the end of the 1st week of November, most chicks had already fledged and left the breeding colony.
- Based on the observed petrel fledging dates within our monitored sites, the fledging timing pattern has been similar to that of Haleakalā National Park (HNP) data throughout the monitoring period, indicating that construction has not had an impact on the nesting cycle.
Rodent and Predator Monitoring: (Not required by the HCP or BO)
|
Table 4. Number of Pictures of Different Identifiable Animal Categories Captured by DKIST HCP Monitoring Camera Traps. |
|
||||||
|
|
|
||||||
|
Site |
Year |
Goat |
Bird2 |
Rodent3 |
Human4 |
Cat |
|
|
Control |
20131 |
476 |
3 |
0 |
1 |
0 |
|
|
2014 |
938 |
39 |
6 |
0 |
0 |
||
|
2015 |
485 |
23 |
0 |
0 |
0 |
||
|
2016 |
192 |
16 |
0 |
0 |
0 |
||
|
20175 |
44 |
1 |
0 |
6 |
1 |
||
|
Conservation |
20131 |
61 |
11 |
0 |
6 |
0 |
|
|
2014 |
0 |
29 |
1 |
29 |
0 |
||
|
2015 |
0 |
16 |
0 |
16 |
0 |
||
|
2016 |
0 |
13 |
0 |
14 |
0 |
||
|
2017 |
0 |
12 |
0 |
9 |
0 |
||
|
1: initiated in April 2: mostly Chukars (Alectoris chukar), with a few Pacific Golden Plovers (Pluvialis fulva) 3: unidentified rodent species 4: including DKIST personnel
|
|
||||||
Results
Hawaiian Petrel Reproductive Success
- As new burrows were located each year, the number of burrows monitored increased from 272 in 2011 to 392 in 2017.
- 2017 was the first year that no new burrows were recorded in the Control Site
|
Table 1. Hawaiian Petrel Burrows and Reproductive Success in DKIST HCP Conservation Area and Control Site on Haleakalā, Maui, Hawaii (Cons. =Conservation Area, Cont. =Control Site). |
||||||||||||||||
|
|
Year |
2011 |
2012 |
2013 |
2014 |
2015 |
2016 |
2017 |
||||||||
|
Status |
Location |
Cons. |
Cont. |
Cons.1 |
Cont. |
Cons.2 |
Cont. |
Cons.3 |
Cont. |
Cons.4 |
Cont. |
Cons. |
Cont. |
Cons. |
Cont. |
|
|
Old Found in prior years) |
Active |
73 |
0 |
140 |
6 |
122 |
7 |
158 |
7 |
154 |
7 |
106 |
8 |
163 |
10 |
|
|
Successful |
24 |
0 |
16 |
0 |
26 |
0 |
42 |
1 |
29 |
2 |
48 |
0 |
50 |
0 |
||
|
Non productive |
49 |
0 |
124 |
6 |
96 |
7 |
116 |
6 |
125 |
5 |
58 |
8 |
1135 |
10 |
||
|
Not Active |
38 |
0 |
103 |
15 |
151 |
18 |
128 |
19 |
143 |
22 |
200 |
23 |
169 |
23 |
||
|
Not a Burrow |
10 |
0 |
15 |
0 |
8 |
0 |
2 |
0 |
0 |
0 |
5 |
0 |
0 |
0 |
||
|
New (found during year) |
Active |
86 |
14 |
13 |
3 |
3 |
1 |
7 |
3 |
14 |
2 |
13 |
2 |
26 |
0 |
|
|
Successful |
8 |
0 |
0 |
0 |
1 |
0 |
2 |
0 |
0 |
0 |
1 |
0 |
3 |
0 |
||
|
Non productive |
78 |
14 |
13 |
3 |
2 |
1 |
5 |
3 |
14 |
2 |
12 |
2 |
23 |
0 |
||
|
Not Active |
39 |
7 |
9 |
1 |
3 |
0 |
1 |
0 |
0 |
0 |
8 |
0 |
1 |
0 |
||
|
Not a Burrow |
5 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
||
|
Subtotal |
Old |
121 |
0 |
258 |
21 |
281 |
25 |
288 |
26 |
297 |
29 |
311 |
31 |
332 |
33 |
|
|
New |
130 |
21 |
22 |
4 |
6 |
1 |
8 |
3 |
14 |
2 |
21 |
2 |
27 |
0 |
||
|
Total |
251 |
21 |
280 |
25 |
287 |
26 |
296 |
29 |
311 |
31 |
332 |
33 |
359 |
33 |
||
|
Nesting Activity % |
67.37 |
66.67 |
57.74 |
36.00 |
44.80 |
30.77 |
56.12 |
34.48 |
54.02 |
29.03 |
35.84 |
30.30 |
52.65 |
30.30 |
||
|
Nesting Success % |
20.13 |
0.00 |
10.46 |
0.00 |
21.60 |
0.00 |
26.67 |
10.00 |
17.26 |
22.22 |
41.18 |
0.00 |
28.04 |
0.00 |
||
|
1. Seven of the old burrows recorded in 2012 were burrows that were marked prior to 2011, but were found in 2012. 2. One of the old burrows recorded in 2013 was marked prior to 2011, but was found in 2013. 3. Including one burrow separated from an old burrow in 2014. 4. Including one burrow separated from an old burrow in 2015. 5. Including two unknown outcomes due to camera failure. |
||||||||||||||||
- In the Conservation Area, the largest number of active burrows since 2011 was recorded in 2017.
-
- There were 189 active burrows in 2017, which is a 57% increase over 2016 (119).
- Nesting Activity % (52%) showed a significant increase compared to 36% in 2016 (χ2 =7.617, P<0.05, df=1, Figure 8)
- The successful burrow number increased 8% to 53 in 2017
- Nesting Success % (number of fledglings/number of active burrows) increased 77.5% after the conservation measures were implemented in the Conservation Area
- “Nesting Success %” was 28.0%, somewhat lower than it was in 2016 (41.2%, χ2 = 2.801, P>0.05, df=1) (Figure 10).
- The annual Hawaiian Petrel productivity (number of chicks produced) in the Conservation Area increased 82.3% after the HCP was fully implemented
Hawaiian Petrel Mortality
In order to better quantify the annual benefit to the population, we first determined the expected mortality rate for both chicks and adults, respectively.
The annual chick/adult benefit is the difference between the expected mortality and the actual number of mortalities recorded each year. Finally, these annual benefit values for years 2013-2017 were summed to determine the total Net Recovery Benefit.
As of the end of the 2017 season, it is estimated that the predation of 22 chicks and 12 adult Hawaiian Petrels has been prevented due to the predator control measures implemented by the DKIST Project. This net reduction in predation of 34 birds represents a significant Net Recovery Benefit to the species (Table 2).
|
Table 2. Hawaiian Petrel Predation Rates Before (2011-2012) And After (2013-2017) DKIST Mitigation Efforts in the DKIST Conservation Area at the Summit of Haleakala, Maui. |
||||||||
|
Year |
2011 |
2012 |
2013 |
2014 |
2015 |
2016 |
2017 |
Total |
|
Active Burrows |
159 |
153 |
125 |
165 |
168 |
119 |
189 |
|
|
Chicks Produced |
38 |
17 |
30 |
44 |
29 |
49 |
54 |
|
|
Chicks Fledged |
32 |
16 |
27 |
44 |
29 |
49 |
53 |
|
|
Chicks predated |
6 |
1 |
3 |
0 |
0 |
0 |
1 |
|
|
Expected Chick Predation at 12.7% |
|
|
3.82 |
5.60 |
3.69 |
6.24 |
6.87 |
|
|
Annual Chick Benefit |
|
|
0.82 |
5.60 |
3.69 |
6.24 |
5.87 |
22.22 |
|
Annual Chick Predation Rate |
0.16 |
0.06 |
0.10 |
0.00 |
0.00 |
0.00 |
0.02 |
|
|
Adults predated |
1 |
3 |
0 |
1 |
0. |
1 |
1 |
|
|
Expected Predation at 3.6% |
|
|
2.18 |
3.20 |
2.11 |
3.56 |
3.93 |
|
|
Annual Adult Benefit |
|
|
2.18 |
2.20 |
2.11 |
2.56 |
2.93 |
11.98 |
|
Annual Adult Predation Rate |
0.01 |
0.009 |
0.00 |
0.01 |
0.00 |
0.01 |
0.01 |
|
- In 2017, 6 of the 20 burrows being monitored by cameras were successful in fledging petrels. We also installed 84 camera traps at active burrow sites outside of the Mees Observatory area (including 7 in the Control Site). Among these camera traps, the exact fledging dates at 47 burrows were recorded. Based on 53 fledging date recordings, the fledging dates were between October 4 and November 4 (median date: October 21) (Figure 17).
- The recorded events of 2017 confirmed that Hawaiian Petrels begin fledging from their burrows during the latter part of September, as has been the case in previous breeding seasons. The 3rd and 4th weeks of October accounted for the largest number of fledged chicks. By the end of the 1st week of November, most chicks had already fledged and left the breeding colony.
- Based on the observed petrel fledging dates within our monitored sites, the fledging timing pattern has been similar to that of Haleakalā National Park (HNP) data throughout the monitoring period, indicating that construction has not had an impact on the nesting cycle.
Rodent and Predator Monitoring: (Not required by the HCP or BO)
|
Table 4. Number of Pictures of Different Identifiable Animal Categories Captured by DKIST HCP Monitoring Camera Traps. |
|
||||||
|
|
|
||||||
|
Site |
Year |
Goat |
Bird2 |
Rodent3 |
Human4 |
Cat |
|
|
Control |
20131 |
476 |
3 |
0 |
1 |
0 |
|
|
2014 |
938 |
39 |
6 |
0 |
0 |
||
|
2015 |
485 |
23 |
0 |
0 |
0 |
||
|
2016 |
192 |
16 |
0 |
0 |
0 |
||
|
20175 |
44 |
1 |
0 |
6 |
1 |
||
|
Conservation |
20131 |
61 |
11 |
0 |
6 |
0 |
|
|
2014 |
0 |
29 |
1 |
29 |
0 |
||
|
2015 |
0 |
16 |
0 |
16 |
0 |
||
|
2016 |
0 |
13 |
0 |
14 |
0 |
||
|
2017 |
0 |
12 |
0 |
9 |
0 |
||
|
1: initiated in April 2: mostly Chukars (Alectoris chukar), with a few Pacific Golden Plovers (Pluvialis fulva) 3: unidentified rodent species 4: including DKIST personnel
|
|
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