In the pre-dawn hours of July 3, 1983, 58-year-old Senia Marie Mattson was with family and friends at a cabin in Trout Lake Township, Michigan. The cabin was situated on the western shore of Carp Lake, also known as Trout Lake, a setting that would soon become the focal point of a lasting mystery. Reports indicate that after consuming a significant amount of alcohol, Senia left the cabin around 4 a.m. and walked into the surrounding woods.
She has not been seen or heard from since that early morning. The gathering was meant to be a time of connection, but it tragically marked the last time anyone would see Senia.
At the time she vanished, Senia was described as a white female with brown hair and green eyes, standing 5 feet 4 inches tall and weighing approximately 140 pounds. She wore prescription eyeglasses. Her clothing consisted of blue jeans, a light blue sweatshirt, and maroon tennis shoes. She was also wearing a gold wedding band and a gold watch with a gold band. Senia had several distinguishing physical features, including scars on both breasts from mastectomies and a scar on her left upper arm from a tattoo removal. Authorities were also informed that she suffered from periodic memory lapses, a detail that added another layer of concern to her abrupt disappearance.
In the wake of her disappearance, extensive air and ground searches were launched in the dense woods surrounding Carp Lake, but they yielded no trace of Senia. Investigators have been left with few clues, considering possibilities that she may have become lost in the wilderness or perhaps accepted a ride from someone. Despite the passage of decades, the efforts of the Michigan State Police have not brought a resolution to her case. This lack of answers has left her family and community in a state of prolonged uncertainty. The case of Senia Marie Mattson is an enduring mystery, a story of a woman who stepped into the woods one summer morning and seemingly vanished without a trace, leaving behind only questions and the quiet hope for discovery. Her case remains open and is listed in national missing persons databases.
Senia Marie Mattson was a 53-year-old white female who was last seen on July 3, 1983, in Trout Lake Township, Michigan. Public missing-person records describe her as 5 feet 4 inches tall and approximately 140 pounds, with brown hair and green eyes. She wore prescription eyeglasses, and at the time she vanished she was reportedly wearing a light blue sweatshirt, blue jeans, maroon sneakers, a gold watch, and a gold wedding band. Her identifying medical details included scarring from a complete mastectomy of her right breast and a partial mastectomy of her left breast, as well as a scar on her upper left arm from a tattoo removal.
The known account of Senia’s disappearance begins at a cabin on the shores of Carp Lake in Trout Lake Township. According to The Charley Project, after drinking a large amount of alcohol, Senia left the cabin and walked into the woods. She was never heard from again. The public record does not provide a detailed sequence of what happened immediately afterward, and it does not identify a confirmed later sighting, a phone call, a discovered trail, or any explanation for why she did not return from the wooded area.
Other online sources tied to NamUs preserve the same basic outline of the case: Senia was last seen in Michigan’s Upper Peninsula near St. Ignace, and she left a cabin along Carp Lake on foot after consuming a large amount of alcohol. Uncovered lists the NamUs number associated with her case as MP9786 and records her as a white or Caucasian female, with a listed height of 64 inches, weight of 140 pounds, and brown hair. That source lists her age at the incident as 58, while The Charley Project lists her age as 53, creating a discrepancy in the public record. Because the available sources differ on age, the details should be read with care, though both sources agree on the date, location, and general circumstances of her disappearance.
The landscape surrounding the case adds to the concern. Senia did not disappear in a city setting where someone might easily notice her movement; she vanished after walking into woods near a lake in Michigan’s Upper Peninsula. In such a setting, the absence of later contact carried immediate danger, especially given the report that she had been drinking heavily before leaving the cabin. The public summaries do not describe the results of searches in detail, and they do not indicate that any personal belongings, remains, or definitive evidence were found. What remains available online is a short, painful account of a woman last seen alive near Carp Lake and then lost to the surrounding woods.
Senia Marie Mattson’s case remains publicly documented as endangered missing, with the Michigan State Police listed as the investigating agency. The surviving online record is compassionate but sparse, preserving her name, her appearance, her clothing, her medical identifiers, and the final known circumstance that she left a cabin on the shores of Carp Lake and walked into the woods on July 3, 1983. In overview, Senia Marie Mattson was a female last seen in Trout Lake Township, Michigan, on July 3, 1983; she was listed by The Charley Project as 53 years old, white, 5 feet 4 inches tall, 140 pounds, with brown hair, green eyes, prescription eyeglasses, and distinctive scarring, and her disappearance remains a long-running missing-person case with few publicly released details and no clearly documented public resolution in the online sources reviewed.Last Seen: Jul 3, 1983
