Little Silver Point Osprey Camera


This is a live stream of a video of an osprey nest on Little Silver Point in Little Silver, NJ. While stable for several weeks it may be down aperiodically for maintenance and updates. If your video stops try reloading the page a little later.

Nest Location

Live video of osprey nest.
Static image of back yard captured once per minute. Note nest to right of tree.

URL

The following URL for this site supersedes others used during site startup. This is the only one that should now be used.

https://osprey.wrwetzel.com

Bird Names

We have not given the birds names yet.

Gender Determination

Female ospreys are up to 20% larger than males. This is handy if you have a pair sitting together but not so helpful if you only have one bird in view. The main useful visual clue is the bib or necklace marking on the chest. Adult females tend to have quite pronounced brown necklaces while adult males have a lighter marking, sometimes fading to virtually nothing.

Incubation Period

One online osprey blog includes the following explanation:

A three-egg clutch takes about 6-7 days to complete; a 4-egg clutch probably 8-10. The Eastern Bay Osprey Cam has allowed precise documentation of this timing; even in one case the time of day the egg was laid. Incubation begins with the first egg, so the eggs hatch in sequence. Marked eggs typically hatch in 37-38 days.

Image Background

The the camera is pointing 20° east of north. Little Silver Creek, the water in the background of the video, has a maximum fetch to the east of about 2 miles through an range of headings of 60° to 90°. Waves moving right to left are coming from this direction. Fetch to the north is about .14 miles at a heading of 90°, too small to produce any significant wave action. Maximum fetch to the west is about .5 miles at a heading of 275°. Waves from this direction are moving left to right.

On the weekend of 18 May 2019 my neighbor moored a Sanderling sailboat behind his house. It may appear in the background of the image, possibly moving as it sails the mooring, depending on its position relative to the camera and nest. Although it appears close because of perspective distortion (from the telephoto lens) it is actually about 200' offshore.

Lighting Levels

The camera sensitivity is a bit less than the human eye. The video will go dark a little earlier in the evening than the nest does to the eye and the video will show again in the morning a little later than to the eye. No artificial illumination, visible or IR, will be used to avoid interference with the osprey circadian rhythm. The camera has brightness controls, which have not been explored.

Significant Events

We are planning to log nest observations in Nesting Diary at the Nest #7519 page of Osprey Watch. Independent of that here are a few significant events:

Image Quality

The camera is indoors, shooting through a window, and is about 225' away from the nest. Shooting through the window is sub-optimal and introduces some impairments in the image but fewer than would occur if the lens, camera, and computer were exposed to the elements through an open window. There is shimmering on some days depending on the air and sun conditions. This is due to atmospheric refraction from temperature differences in the air between the camera and the nest. Of course when it is raining there will be rain on the window and in the space between the camera and nest.

Audio

Regretfully there is none. The birds can be seen vocalizing and it would be great to capture it but we have no microphone, power, or wi-fi nearby.

Technology

This uses a Raspberry Pi (RPi) camera mounted near the film plane of a discarded Nikon Nikkormat camera and Nikkor 35mm camera lenses. The size of the diagonal of the RPi camera sensor and a 35mm camera are 4.59mm and 43.27mm respectively yielding a equivalent focal-length ratio for a 35mm camera lens on the RPi camera of 9.41. A 200mm (35mm camera) lens has an equivalent focal length of ~1900mm. With this lens the nesting box just about fills the frame of the image and the perches on either side of the box are out of view. This is an angle of about .7 degrees for the horizontal of the image. A 85mm lens has an equivalent focal length of ~800mm. This shows the box and perches with a little margin on each side. Various focal lengths were explored before settling on a 200mm lens for best nest detail at the expense of not showing the perches.

The RPi camera is connected to a Raspberry Pi 3, which presently serves the video directly to viewers through a home network. It is unclear how many simultaneous users this can support and if another approach will be necessary. Note that while the video comes directly from the RPi this web page is hosted at a cloud-based virtual server.

The Modified Nikkormat

Here are a few photos of the camera used for the live video.

Completed camera with RPi attached to body.
Body showing duct tape to keep dust and light out.
RPi Camera through lens mounting ring.
RPi Camera attached to rear door. Film pressure plate removed from four studs near camera.

Links

The nest is registered with Osprey Watch. See the Nesting Diaries section of Nest #7519 for a journal of nesting activity.

There are several photos of the nest and osprey in an album at Flickr.

The design for the nesting platform came from New Jersey DEP. It is an elegant, simple design which took two people about three hours to build. The hardest part was erecting the completed nesting box/pole assembly. That took four people working at about the limit of their strength.

We use this date calculator to estimate the incubation period.